Diamond
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Black diamond, blue diamond, certified diamonds, diamond and pearl, diamond
mine, diamond jewelry, diamond earrings, diamond ring, loose diamonds, wholesale,
pink diamond.
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-Diamonds come in all colors just like a
rainbow and there is no black diamond.
What about
some marvelous blue diamond
for your big love, should be certified
diamonds, we never know, or ? The absolute
hit in diamond this days are pink diamonds,
should be from the Argyle mine. Maybe
square pink diamond in princess cut finish,
princess cut diamond and carrot
diamond of various
colors are
the ultimate present for your darling, but
think about it what will happen when she
find another darling and you are put
to the love trash.
Pink
diamonds are so beautiful, they come in all
kind of cuttings.
Maybe as pink diamonds band, great pink diamonds
engagement rings, pink diamonds jewelry of any
kind and that very special pink
diamond cut ring.
Diamonds are the girls best friends, we
know, since DeBeers say this, but the
cute girl don't want
clear uncut raw diamond, she wants pink
heart cut diamonds and
princess cut
diamond,
this are definitely not
forbidden diamonds.No need to be the Lesotho
promise diamond, since not
even the Queen of England can pay that, just
a cute pink diamond ring for some millions of euro, we don't go for dollars or
rupees this days, who want to be a cheap
charley ?
And don't come up with clarity
enhanced diamonds
with sometimes pushed color or unnatural
colored diamonds. Cubic Zirconium, the
Russian form of diamonds is also out of
question.
What about some diamonds
earrings within a great platinum frame, he
man ! be nice to your girl. She makes it
special for you
afterwards.
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Diamonds plus Science, History, and Worldwide
Localities of Diamonds
Natural diamonds
crystals are among the most elegant and
charismatic of mineralogical collectibles,
but they are relatively rare in collections
because of |
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their high value as gemstones,
their typically rather small size and their
limited availability outside of the gem
trade. Currently the fashion is
princess cut, diamond, pink diamond, pink
diamond band and pink diamond engagement
ring, plus pink diamond jewelry. Pink
diamond rings are the right stuff for the
girls.
Natural diamonds also represent a rich and
extensive cultural history, a broad
geographical distribution, and a fascinating
geological history still being puzzled out
by researchers, but this days we also have
created diamonds
from the lab.
Diamonds have been found on every continent
in the world, with the possible exception of
Antarctica, and have been mined from hundreds of deposits worldwide since at
least 800 B.C.
Enormous diamonds stockpiles are held
in reserve by DeBeers, the preeminent
clearinghouse for world diamonds, and by the
Russian Diamond Fund. Diamonds can hardly be
said to be a rare mineral, despite its
traditionally high market value. Despite
this seeming abundance of diamonds over the
centuries, and the presence of at least
token crystals in many 18th and 19th-century
mineral collections (some of which are
illustrated here for comparison), relatively
few collectors, especially in recent times,
have ever attempted to specialize in the
species. The price manipulation of diamonds
is done via a cartel were DeBeer is the
mastermind, its a puzzle, at lest to me, why
the anti cartel office in Brussels is not
doing anything since DeBeers is listed at
the London stock exchange. I wonder who is
pocketing money at Brussels for closing the
eyes.
One of the early diamonds
specialists was the British collector
Sir Abraham Hume (1749-1838), whose fine
collection of 107 diamond stones was
cataloged by Count de Bournon in 1815.
Another early British collector, Charles
Hampden Turner (whose mineral collection was assembled for
him by the mineral dealer Henry Heuland),
possessed 109 examples of diamonds. Armand
Levy, who prepared Turner's published
diamond collection catalog in 1838, remarked that it
was impossible to identify the locality for
any given diamond crystal based on its habit
alone, and so localities were generally not
cited in the catalog.
Levy guessed that
most of Turner's diamonds crystals were
probably from Brazil. This days the real big
diamond stones come from Lesotho
in southern Africa. |

Princess cut diamond ring |
- Fashion in diamonds
is now definitely pink diamond
and princess cut ,
they
come in many variants like pink
diamond band, pink diamond
engagement ring, pink diamond
jewelry with princess cut.
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Pink
Diamond Ring |
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Diamonds come as diamond
earrings, diamond bracelet,
diamond pendants, diamond
ring, pink diamonds, blue
diamonds, diamond cut,
diamond gold, color diamond,
diamond, blue diamond,
diamond jewelry, diamond
necklace, diamonds rings,
black diamond, pink diamond,
round diamond and emerald
cut diamond. |
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Especially princess cut diamonds
such as earrings,
princess cut diamonds
engagement rings, diamonds pendant,
diamond stud
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Pink Diamond Ring 28 carat |
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earrings or just princess
cut loose diamonds are
very popular.
Some
more: Square pink diamonds,
carrot diamond, pink diamond, pink
diamond band,
pink diamond engagement ring, pink
diamond engagement rings, pink
diamond jewelry, pink diamond ring,
pink diamond rings.
Princess cut diamond earrings are
presently the most popular diamond
earrings. The choice is princess
cut diamond earrings with a colored
diamond or a pure white diamond.
Some smaller diamonds could be set
around the center diamond. It also
could be mixed with some emeralds,
looks real great.
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Naturally the larger the diamonds
the more expensive the princess cut
diamond earrings are. That means
make sure there is enough cash on
your account, its getting expensive,
trust me.
After finding the right princess cut
diamond earrings ask the jewelry
shop if they can supply a
insurance too, its easy to loose
this expensive |

Princess cut diamond
earrings |
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diamond
jewelry since its not big stuff in
terms of size.
You
will find our quickly that the
princess cut diamond earrings fits
almost with anything you wear.
They look beautiful and |
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you will
be the focus of attention,
especially with your friends. As it is said
diamonds are the girls best friends,
this especially is valid for this
pair of great princess cut diamond
earrings (diamond picture above
right), they will never go out of
style.
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Shining Transparent Diamond Stone:
A
500-carat white diamond
discovered in a diamond mine in the
Kingdom of Lesotho in South Africa
was one of the largest diamond ever
discovered.
On 8
September 2008, mine workers in the
Letseng mine of Lesotho the
magnificent piece of Diamond was
digged out from the earth in
Lesotho. It
is one of the largest and
purest diamonds ever
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Diamond discovered in
Lesotho |
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discovered. A similar Diamond stone
was recently found .and
estimated to have a value of
about 12 million U.S. dollars.
The new discovered
diamond in Lesotho is even
more pure and has presumably
more value. The Lesotho
diamond could be cut to a
150 carat diamond and thus
more valuable than any of
the British Crown Jewels:
The gemstone Koh-i-Noor, the
British seized in the 19th
Century in India has 105
carats.
The most valuable diamond
so far is the Great Star of
Africa with 530 carats.
The drop-shaped gem was cut
and polished from the 1905
discovered Cullinan Diamond,
this diamond had 3106 carats
as a raw diamond stone. The
Letseng mine in Lesotho
belongs to 70 percent to the
London-registered company
Gem Diamonds and 30 percent
to the government of
Lesotho.
The extravagant Ecuadorean diamond collector in Paris, Don Pedro
Davilla (ca. 17101775), had a mere 16
diamond crystals in his enormous collection
of over 8,000 total diamond specimens.
The Austrian
banker and businessman Jacob Friedrich von der Null, whose huge mineral collection,
curate by the prominent mineralogist
Friedrich Mohs, was considered to be the
best in Vienna, owned 36 diamond crystals (Mohs,
1804). |

The Lesotho Promise
Diamond cut from one
stone of 603 carats.
26 D color stones in
one necklace from
one jewel |
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Also in Austria, Ignaz von Born
assembled a suite of nine crystals for Mile.
Eleanore de Raab in 1791. In the 20th
century, Paul seel (1904-1982) assembled a
collection of several hundred diamond
crystals, each of which "illustrated some
morphological fact" (Desautels, 1970).
It
was considered by Paul Desautels to be the
finest and largest collection of diamond
crystals then in existence-and considering
his authoritative knowledge of collections
worldwide, we can safely accept his judgment. Such diamonds collections remain rare today,
both because of the high unit cost of good
specimens and because the international
diamonds market is not set up for the
distribution of collector-quality uncut
diamond crystals.
Rough gem-quality diamonds are
normally sold only in parcels which cannot
be cherry-picked for individual pieces. These parcels of diamonds are always purchased
(usually in Antwerp) by commercial cutters
or by dealers in abrasives, who have no
interest in or awareness of diamond crystals
as
specimens.
The weight of
Diamonds is measured in
carat and the |

A rainbow of diamonds colors |
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diamonds clarity is very
important, so is the
diamonds cut. Diamonds de
beers sell loose diamonds
for diamonds earrings,
diamond jewelry with
emeralds, diamonds
engagement rings, a popular
diamonds exchange is in
Antwerp Belgium you can
affordable diamonds there,
in particular African
diamonds, those
pretty stones are the right
material for great diamond
jewelry. Therefore the acquisition of
collector-quality diamonds crystals
normally requires the help of someone who is
either involved in the commercial end of the
diamond trade or who has especially good
personal connections in Antwerp, or both. |
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A 603
Carat Diamond comes from the Letseng
Mine in
Lesotho -
South Africa- named the "Lesotho
Promise". |
Recently the Mineralogical Record was given
access to a remarkable private collection of
diamond crystals. The specimens were
acquired by dealers Jack Greenspan and David
New over the last 20 years or so. Jack
filtered his loose diamonds specimens out of commercial
lots purchased for his business in abrasives
and saw blades; Dave got his through
personal connections with diamond merchants
in Amsterdam, who were willing to set aside
for him a particularly nice single crystal
every once in a while. The private diamonds collector
who acquired the diamond specimens from these
gentlemen was thereby able to assemble an
extraordinary diamond collection. Since such
a loose diamond collection is so unusual, we thought that
Mineralogical Record readers would like an
opportunity to see the loose diamond specimens and learn
something about the geology, cultural
contexts and mining histories of the
localities represented. |
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The crystal forms of the diamonds cover a
familiar range: there are simple
diamond octahedrons, cubes and dodecahedrons,
and there are combinations of these; there
are single crystals and clusters of
crystals, and there are the characteristic,
flattened triangular shapes of "made" spinel-law
twins. Some of the diamond crystal faces are convex
to varying degrees, some are slightly rough,
and inspection with a loupe reveals growth trigons on some. A few
diamond crystals are highly
lustrous and gemmy while others are duller;
inclusions may or may not be naked-eye
visible.
The physical appearance of diamonds,
even large ones, is predictable in many
ways, and yet their historical/cultural and
even geological histories always have a
special fascination. We are talking, after
all, about diamonds: adamas was the Greek
root word, always carrying connotations of
magic powers, invincible strength and the
workings of strong, brazen gods.
Before looking specifically at the
localities for the 52 diamonds pictured here
from the collection, a brief historical
overview of diamond mining and a summary of
the exotic geological "story" that all
localities have in common is in order.
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Some History of Diamonds
Very few modern mineral collections can
boast diamond crystals from India, and
yet the roots of diamond romance and diamond
commerce lie unmistakably there. The world's
"first" diamonds were taken from Indian
riverbeds as long ago, perhaps, as 800 B.C.
(www.diamondcutters.com); a Sanskrit
manuscript, the Artha-Sastra, mentions a
king of the Maurya dynasty (320-298 B.C.)
who regulated an active local diamond trade
(Maillard, 1980). Legends associated with
the invasion of India by Alexander the Great
speak of a "Valley of
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Yellow Diamonds |
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Diamonds," narrow and deep
but laden with gems: men
would kill and flay sheep,
cast quarters of raw flesh
into the chasm, let birds of
prey eat the flesh, then
kill the birds when they
soared out of the chasm,
collecting the diamonds |
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which had
adhered to the feathers. Variations of this
core story spread to China, and later into
the Persian and Arab worlds, reaching Europe
in 1298, when Marco Polo repeated it in his
Book of Marvels.
Other early diamond legends claimed
that Indian diamonds had the power to
neutralize magnetism, and that the most
precious diamonds are those which float in
water (this one is puzzling, given the high
specific gravity of the mineral). Four
general grades of Indian diamonds were
associated in various ways with the four
castes into which classical Hinduism divides
humankind. Diamonds could either poison or
heal, bring bad luck or good.
A myth
repeated by Pliny claimed that the diamond's
"invincible force" can be "broken" only by
applying to the stone the blood of a hegoat:
the myth was later allegorized in Christian
terms, the diamond being identified with
Christ, the he-goat with Satanic powers (Maillard,
1980). |

Blue magic diamond |
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The ancient Romans loved Indian diamonds,
and traded for them with native merchants
around the "Gulf of Cambay" (today, the Gulf
of Khambat, above Mumbai)From the days of
the Roman Republic, through the centuries of
the Empire, the medieval period, and into
the Renaissance, diamonds were brought from
India to Europe via two main trade arteries:
an overland route, passing through Persia
and Byzantium to Rome or Venice, and a
southern route, traversing the Indian Ocean
and running up through Arabia to Alexandria,
and thence to Italy.
In the 17th century,
the French traveler Jean-Baptiste Tavernier
visited some of the Indian diamond mines and
brought back much valuable
information including legends, already richly
textured, about the fabulous Kohi-Noor
("Mountain of Light") diamond. This, the
first of the world's major named diamonds,
reportedly weighed 600 carats originally,
and is now to be seen, facet-cut, in the
crown of the English Queen Mother.
The great
blue "Hope" diamond, now in the Smithsonian,
was also found in India, and is likewise
couched about with ancient mythic tales,
mostly involving the bad luck it brought to
its owners.
A Indian
diamond
was harvested
from alluvial deposits in the gravels of
stream beds, possibly very far from the
primary kimberlite pipes. However, some also
were probably found in loose eluvium just
above a pipe or in colluvial ground adjacent
to it. |

Indian Kundan Bangle from
gold and silver plus
diamonds

Indian Kundan is the Mughal-inspired
art of setting diamond
stones in gold and silver
Indian Diamonds Photo by
devakinandan |
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One Greek account of
about 120 B.C.
speaks tantalizingly
of underground
diamond mines with
deep galleries (Maillard, 1980);
these were probably not mines in kimberlite
but deep diggings in diamond-bearing
conglomerates, called "the pits of Panna"
by Williams
(1905).
Five areas in
India produced diamonds
for jewelry,
and one, the largest and richest, became
famous under the name "Golcondad iamond mines," or
"the Kingdom of Golconda," since the town of
Golconda was its |
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capital and the center of a
large diamond trade (Williams, 1905; Harlow,
1998). all that remains of the opulent
"Kingdom" today is a ruined fort near
Hyderabad, and the only modern producing
diamond mine in India exploits the Majhgawan
lamproite pipe near Panna, producing
annually about 20,000 carats-0.2% of world
output (Levinson et ai, 1992). |
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During the European Renaissance, Dutch
and Portuguese traders competed for Indian
diamonds, while at the same time the
Portuguese, from their infant colonies on
the African coasts, attempted to penetrate
the African interior. The Portuguese hoped
to find the wealth of "Ophir," the legendary
home of the biblical Queen of Sheba and of
King Solomon's mines, whence had supposedly
come the diamonds on the breastplate of
the High Priest of ancient Jerusalem.
Nothing came of these early African quests,
but Indian diamonds meanwhile poured into
Europe along the main internal trade routes
running at first from Venice to Antwerp, and
from Lisbon to Amsterdam.
Around
1464 the "Sancy" diamond from India, then
owned by Charles the Bold, Duke of Burgundy,
was refashioned as a fine facet-cut gem by
"the true artist Louis de Berquem of
Bruges," in modern Belgium (Williams, 1905),
and by the early 16th century a
diamond-cutting industry was beginning to
flourish in Antwerp. Between the 16th and
18th centuries, first Amsterdam, then
London, became the capital of the diamond
world. Although Dutch merchants kept
investing heavily in the Indian diamond
trade, the English by the early 18th century
had acquired near-monopoly control of Indian
diamonds, and had supplanted the Dutch-by
which time, however, the discovery of
Brazilian diamonds brought Portugal once
more into the game. For a full account of
these early-capitalistic maneuvers involving
diamonds, and their entwinements with
European power politics, see Maillard. |

Emeralds and diamonds
necklace and ear rings |
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The era of Indian diamonds ended in 1725,
when some shiny stones found by Brazilian
garimpeiros in an alluvial gold deposit near
the town of Tejuco (now Diamantina), in
Minas Gerais, proved to be diamonds. The
Brazilian era continued until the South
African discoveries of the 1860's, and South
African diamond production monopolized the
field until the first decades of the 20th
century. South Africa is still a significant
producer, but since about 1920 Zaire (now
the Congo Republic), Angola, Botswana,
Russia and Australia, in that chronological
order, have all surpassed it in annual
output. Zaire produces mainly industrial
diamonds, and has been doing so since the
First World War, when the country was known
as the Belgian Congo. Zaire's diamondiferous
region lies near the Angolan border, where
crystals are found in alluvial gravels and
mined from a large kimberlite pipe at
Mbuji-Mayi. This country has been so
prolific since about 1920 that,
surprisingly, it leads the world in total
production, as measured by carat weight, for
the entire period from antiquity to 1990.
Zaire's total all-time
figure is 718,117,000
carats, and South Africa,
with 446,856,000 carats,
comes in second (Levinson et
al, 1992).
Kimberlite pipes were
first prospected in the Yakutia Craton of
northeastern Siberia,
Russia, after World War II.
There are three major
diamond-producing fields
here: the adjacent Daldyn
and Alakit fields and, about 400
km to the south, the Malaya Botuobiya field. In the summer of 1955, within ten
days of each other, the Udachnaya
("success") kimberlite was discovered in Daldyn, and the Mir ("peace") kimberlite was
discovered in Malaya-Butuobiya. These
diamond occurrences have become fairly well known to
mineral collectors, as small numbers of
their matrix specimens of diamond crystals
in kimberlite have reached western collector
markets (Sullivan, 1978; Moore, 1995). The
mine at Mir is now idle and flooded, but
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Udachnaya continues to produce diamonds, as
does a very large pipe called jubilileynaya
("Jubilee").
The Yakutia Craton is now the
world's second most productive geological
province for gem-quality diamonds, after the
Kalahari Craton in southern Africa (Harlow,
1998).
Diamonds from the United States have
been nothing more than small
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sideshows on the world scene.
The "Crater of Diamonds" at
Murfreesboro, Arkansas remains a popular
site for tourist diggers in loose "dry
ground"; diamonds were first found there in
1906, above what was first called a kimberlite, but is now known to be a
lamproitc diatreme (Kidwell, 1990). In the
early 1960's, some kimberlite diatremes in
Laramie County, Colorado and adjacent parts
of Wyoming were found to be diamondiferous
(Collins, 1982), and 327 carats' worth of
small octahedral crystals were recovered in
the early 1990's (Moore, 1997). California
also hosts at least one primary deposit, at
Leek Springs near Jamestown.
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Vastly more
promising for the future are the diamonds
of Canada a country which bestrides the enormous
North American cratonic region, and where,
given the vastness of the potential ground,
exploration still must be said to be in its
early stages. Kimberlite swarms have been
located in Saskatchewan and Alberta, but the
real excitement during the late 1990's was
occasioned by the discovery of
diamondiferous diatremes lying around and
under Lac de Gras, in the Arctic wilderness
of the central Northwest Territories: see
Kevin Krajick's recent book Barren Lands
(2001) for an exciting account of events
leading to the opening of the Ekati diamond
mine there, in 1998. Beautiful flower design
of a diamond brooch at the picture.
Presently Venezuela, Guyana, Indonesia,
Liberia, Ivory Coast, Lesotho and Swaziland
all produce some diamonds; and alluvial
mining in the northwestern part of Hunan
Province, China has recently yielded a
beautiful 1.2-cm made twin which appeared in
Tucson around ten years ago (Moore, 1993).
- The Origins of Diamonds
Before the latter half of the 19th century,
all diamonds were mined from alluvium: the
antique crystals from India and Brazil had
been found in sediments, loose or lithified,
and science had no idea of how the mineral
formed in its native rock, or indeed what
that rock might be. But the great South
African diamond discoveries in the 1860's
revealed the rare rock type kimberlite to be
the true home of diamonds. The first gem
crystals were found loose in the so-called
"yellow ground" of weathered kimberlite, and
soon the unaltered "blue ground" below was
found to contain riches too.
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Diamond brooch
flower design |
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Kimberlite is typically a greenish gray,
chowdery-looking igneous rock formed from a
magna very rich in volatiles (chiefly CO2
and H2O). The rock is composed of large,
irregularly shaped fragments chaotically
mixed in a fine-grained groundmass. Whether
these "fragments" are phenocrysts
crystallized directly from the kimberlite
melt or xenolithic inclusions of other rock
types was a question which went unresolved
for some decades. |
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Blue diamonds, blue
Nile diamonds,
buying diamonds,
Canadian diamonds,
Cartier diamonds,
clarity of diamonds,
coast diamonds,
color diamonds,
conflict diamonds,
brilliant rings, crater of diamonds,
created diamonds,
cultured diamonds,
cushion.
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Round brilliant rings |
- Kirkley et al. (1991) define kimberlite as
follows:
A hybrid, volatile-rich, potassic,
ultramafic igneous rock derived from deep in
the earth (>150 km below the surface) which
occurs near the surface as small volcanic
pipes, dikes and sills [the latter two
structures are very rare]. It is composed
principally of olivine . . . with lesser
amounts of phlogopite, diopside, serpentine,
calcite, garnet, ilmenite, spinel, and/or
other minerals; diamond is only a rare
constituent. Research eventually established that
diamonds come from the included bodies in kimberlite, not from the groundmass; that
these bodies are xenoliths, not phenocrysts;
and that the xenoliths (and, therefore, the
diamonds) are much older than the kimberlite
which carried them to the surface.
A deep-seated origin for kimberlite was
suspected by early investigators, not only
because of its composition, but also because
it was found in South Africa as great,
carrot-shaped "pipes," the point of the
carrot connecting with a system of "feeder"
fissures reaching to unknown depths. Of the
South African kimberlites exploited by the
first mines, some were much more deeply
weathered than others, but the general shape
of these peculiar structures soon became
apparent by comparing what could be seen in
the various workings. Three general zones of a
typical kimberlite diamond pipe
have been distinguished. (1)
The root zone, from the point of the carrot
two or three kilometers down and below,
generally marks the lower limit of
economically profitable mining (even when
erosion |
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has brought the root
near the surface, the volume
of ore is scant). But the
pinch-out of the structure
is never quite complete; the
feeder system is now
believed to reach to depths
of at least 150 km, i.e.
well into the upper mantle.
(2) The main body of the
pipe widens upwards, and is
composed of highly brecciated kimberlite and
other rock types. The
breccia fragments come from
the country rocks through
which the pipe has
passed, and from earlier pulses of the kimberlite which hardened before later
pulses shattered it during the explosive
release of gases. At the top of the pipe,
(3) the crater zone originally consisted of
a low-relief crater called a maar. This
crater area, if it still exists, may be
water-filled and may contain substantial
amounts of weathered kimberlite "yellow
ground." Around the shallow maar craters on
the surface there was originally a ring of
volcanoclastic debris, called a "tuff ring,"
about 50 meters high. In most deposits this
ring is now gone-it has been observed only
in a few places in Tanzania and
Botswana-because the diamond deposits are of great
age and the clastic debris weathers away
very quickly. In fact, kimberlite rock
generally weathers quickly: hence the
considerable thickness of many yellow-ground
beds where the "dry diggings" of South
Africa's early diamond rushes took place.
The ascent of kimberlite
through overlying
rocks is classified
broadly
as a volcanic event,
although kimberlite magma clearly
originates at much greater depths than do
the more common
basaltic and
granite magmas.
Because these types
of bodies are so
different from
ordinary volcanic
pipes they have been
given a different
name: diatremes. Since no kimberlite diatremes
have
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been
observed in the process of eruption during
man's time on earth (the youngest ones
known, in Namibia and Tanzania, date from
the Eocene, i.e. at about 55 million years
ago), it was a challenge to the imaginations
of early investigators to try to picture the
eruptive events. With self-conscious
vagueness Alpheus Williams (1932) wrote that
the kimberlite extrusions "never existed as
volcanoes as we understand true volcanoes,
but . . . they existed, at all stages, as
eruptive fissures." The currently accepted
picture is that kimberlite is emplaced as a
slurry of brecciated, gas-rich material
which, though originally molten at depth,
rises explosively through the pipe as a
"cold" solid, with multiple pulses of new
material shattering already solidified
material above. The overall speed of ascent
is a fantastic (geologically speaking) 10 to
30 km per hour.
At the point in the main
body of the diatreme where pressure drops
enough to allow the dissolved volatiles to
come out of solution, the slurry becomes
effectively jet-propelled, rising at
velocities of several hundred kilometers per
hour during the final few hundred meters (Kirkley
et al, 1991). Thus the diamonds transported
from where they had rested in "storage" for
perhaps 3 billion years at the bases of
continental cratons (see later) reach the
surface in an ascent that takes only four to
fifteen hours (Kirkley et al., 1991). The
eruption climaxes in near-surface explosions
of expanding gases and spewings of
volcanoclastic debris that any observers
present would have found extremely dramatic. That the kimberlite which fills the upper
parts of the pipe arrives "cold,"
rather than as |
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lava, is shown by the fact that
there are no indications of thermal effects,
such as contact metamorphism, along the
walls of the pipe. Furthermore, in some
diamond deposits described by Williams
(1932), unburned tree trunks and other
organic material that collapsed into the
crater and became embedded in the kimberlite
as it surged up and down have been
encountered at considerable depths.
It is interesting to note that diamonds
which reach the surface via the kimberlite
fast-express are metastable (which is to say
that all diamonds we have are metastable):
they only remain diamonds, instead of
disintegrating or pseudomorphing to
graphite, because their rate of
ascent was too fast to allow
re-equilibration. A small kimberlite
pipe at Beni Bouchera, Morocco
has yielded fairly sharp,
multi-centimeter-sized octahedral "crystals"
of graphite |

Yellow square diamond ring 60 carat |
|
paramorphic after diamond:
presumably the rate of ascent in this
particular pipe was slow enough to allow the
crystallographic reorganization to take
place (Bob Downs, personal communication,
2002).
A second rock type, lamproite, which
likewise erupts from great depths to form
pipes, can also be diamondiferous. Lamproite
is less gas-rich than kimberlite and its
eruptions are less violent; the near-surface
configurations of lamproite pipes tend to be
wider (champagne-glass-shaped) than those of
kimberlite (Harlow, 1998). Lamproite is also
somewhat different mineralogically (see the
later discussion of the Argyle mine in
Australia), although the diamonds in the two
rock types do not seem to differ in any
important way. Lamproites, like kimberlites,
occur in the continental cratons, or on
their margins, and, also like kimberlites,
range very widely in age: the Argyle
lamproite pipe is about 1,200 million years
old, but the |
| |
Ellendale lamproite pipe, only
400 km from the Argyle, was intruded
in the Miocene, only 20 million
years ago (Kirkley
et al., 1991).
But where and how do the diamonds originate?
This was the mystery which a great number of
theorists began trying to solve as soon as
the South African kimberlite pipes were
discovered. When, in 1905, De Beers
general manager Gardner F. Williams
published the two volumes of The Diamond
Mines of South Africa, little headway had
yet been made on the question of how and
where diamonds form, but by 1932, when his
son, Alpheus F. Williams, published his own
two-volume work, The Genesis of the Diamond,
three broad classes of theories had evolved. Some geologists argued that the diamonds
crystallized in situ out of kimberlite magma
during the time when the (presumed) magma
was solidifying in the pipe. Geologists also thought that diamonds
crystallized out of kimberlite, but argued
that they did so at depth, before
the ascent of the pipe. |

Pink diamond 5.11 carat |
| |
A third school held that the
diamonds formed at depth in ultramafic rocks
other than kimberlite, and were later caught
up in the kimberlite melt, as constituents
of xenoliths (Williams, 1932). The first of
these theories was a casualty of the
realization that near-surface kimberlite is
emplaced as a cold solid, not as a magma.
The other two theories remained for several
more decades in active contention, being
called informally the "phenocryst school"
and the "xenolith school" (Kirkley et al.,
1991). Alpheus Williams himself adhered to
the phenocryst school, presenting at great,
careful length in his book the argument that
the large included fragments in kimberlite
are of essentially the same composition as
the fine-grained groundmass, i.e. that the
fragments are cognate, not xenolithic.
However, the debate is now settled: the
fragments are indeed xenoliths, and diamond
crystals are not products of the kimberlite
but, as components of xenoliths, are mere
passengers on the kimberlite fast-express to
the surface. This triumph of the xenolith
school is a product of two basic
lines of mid to late 20th-century
research: (1) petrological study of the xenoliths
themselves, as correlated with evolving
knowledge of the earth's mantle and of
plate-tectonic processes, and (2) modern
analytical studies utilizing sophisticated
instruments for the investigation of the
mineral components of the inclusions in
diamonds, and of the ages of these
inclusions.
The xenoliths found in kimberlite (and
lamproite) are of two rock types, both
known to be common in the upper mantle
around and under the continental plates:
eclogite, and a more broadly defined type
generally called peridotite. Eclogite is a
coarse-grained, attractively colored
red-and-green rock consisting of about 50%
garnet (almandine-pyrope) and 50%
clinopyroxene, with minor rutile, kyanite,
corundum and coesite; it is thought to
result from profound metamorphism of
subducted basalt under tectonically active
margins of continental plates (basalt and
eclogite are identical in their bulk
chemistry-Kirkley et al., 1991).
By
contrast, the xenoliths classed as "peridotite"
average about 50% olivine (forsterite), 40%
pyroxene, and 10% garnet. Diamonds are known
to occur in three peridotite subtypes:
dunite (90% olivine), harzburgite (40-90%
olivine, the rest orthopyroxene and garnet),
and Iherzolite (at least 40% olivine, with
orthopyroxene and clinopyroxene in a wide
range of proportions, and minor garnet).
Peridotite of these varying types, as found
just beneath the crust in the stable
interior zones of continents (cratons),
probably is primordial upper-mantle
material, having remained little changed
since the first differentiation of crust
from mantle in the very early earth (see
later). |
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|

37.36 carats of round pink diamonds
in necklace |
Diamonds
which have been brought to the
surface in eclogite or peridotite xenoliths
have come to be called respectively "E-type"
and "P-type" diamonds. Either may be found
still embedded within the host xenoliths or
floating in the kimberlite groundmass after
the fragmentation of xenoliths during the
violent events of ascent.
Eclogite, being
the tougher of the two rock types, is foundmuch more commonly as intact xenoliths in kimberlite at the surface. Eclogite
xenoliths are commonly fresh-looking,
whereas the much rarer peridotite xenoliths
are usually crumbly and/or altered around
their rims. Studies of inclusions in
diamonds have shown that P-type diamonds are
much more common than E-type diamonds, even
though the greater survival rate of eclogite
matrix fragments would seem to suggest the
reverse.
This is one illustration of how the
study of the xenoliths alone can be
misleading unless supplemented by
diamond-inclusion studies. Research on inclusions in diamonds began to
yield hard results in the 1970's, with the
attainment of required levels of
sophistication in X-ray diffraction
techniques, electron and ion microprobe
analyses, and the dating of
trace isotopes (Meyer, 1985; Kirkley
et al., 1991). These minute
inclusions (mostly around 1µm, or
0.001 mm), having been shielded from |
|
later
changes by the enclosing diamond, represent
our best and most pristine samples of
mineral suites from upper mantle rocks.
Although most diamonds show inclusions of
only one mineral species, polymineralic
inclusions are (fortunately) also found.
Thus far, 22 mineral species (including
diamond itself) have been identified as
inclusions in diamonds, and although six of
these may be found either in eclogite or
peridotite, detailed analyses have revealed
two mutually exclusive assemblages of
included minerals, making it possible to
assign 98% of all included diamonds to
either the E (eclogite) or the P (peridotite)
categories (Meyer, 1985).
It has also been possible to draw some
inferences about the temperature and
pressure conditions, and therefore the
depths of diamond formation, in these two
rock types. Correlating with these results
are the isotopic age-dating studies of the
tiny inclusions, which have led to the
approximate dating of the formation of the
host rocks, and therefore the ages of their
diamonds (it is not yet possible to age-date
diamonds directly). Both of these lines of research indicate
that upper-mantle eclogites and peridotites
formed at different times and by different
processes in the deep earth, and that
kimberlite melts at depth may have taken up
diamond-bearing xenoliths from either
environment (or from both), for transport to
the surface. It remains to consider the
nature of these two environments, and to
summarize current thinking which seeks to
correlate the distribution of diamondiferous diatremes with plate-tectonic processes.
Geothermal and geobarometric studies of
e-type
diamonds have shown that these
diamonds have a higher temperature of
crystallization, and form at greater depths,
than P-type diamonds (Meyer, 1985; Kirkley
et al, 1991). Eclogite, as already
mentioned, is characteristic of very deep
parts of subduction zones, well within the
upper mantle below continental platforms,
where the subducted basalt of the former sea
floor metaphorphoses to eclogite. P-type
diamonds, on the other hand, are believed to
form in peridotites of the shallower upper
mantle; they come from depths in the range
of 150-200 km below the surface, whereas
E-type diamonds from one South African mine,
for example, have been assigned depths of
formation of more than 300 km. Radiometrie
dating of trace isotopes of Rb-Sr, Sm-Nd,
and U-Pb in the inclusions has revealed that
all of the diamonds occurring in the
peridotite xenoliths are around 3 billion
years old. This theme of immense age was
also sounded quite early in the modern
history of diamond studies, for it was
realized early that most of the earth's
swarms of kimberlitepipe intrusions occur in
stable continental cratons of Archaean age.
The now-favored model
of the genesis of
P-type diamonds
involves the insight
that "in Archaean
times there was a
unique process
accompanying crustal
formation: a
combination of melt
extraction, fluid
interaction, and
diamond
crystallization that
sometimes left a
relatively cool,
rigid, deep keel
beneath a
continental plate"
(Harlow, 1998). From
the plausible
hypothesis that
these isothermally
defined "keels"
below the cratons
have remained
constant through all
geologic time since
the Archaean, it is
inferred that P-type
diamonds were formed
no later than about
3 billion years ago,
and at depths of
150-200 kilometers.
The question of the
sources) of the
carbon in diamond
has also been
considered. In
carbon-isotope
studies of diamonds,
the term O13C
denotes the ratio of
the carbon isotopes
C12 and C11; these
studies have found
stark differences
between the carbon
in P-type and E-type
diamonds. In the
former, there is a
very tight
clustering of
[delta]^sup 13^C
values within a
narrow range,
whereas in the
latter there is a
much wider
[delta]^sup 13^C
distribution across a broad
range. This is to say that
the carbon in P-type
diamonds had a uniform and
stable source in the upper
mantle: it is thought to be
"primitive" carbon which
accumulated in a stable
convective zone perhaps 4.5
billion years ago, at the
time when the first
continental cratons were
forming. (One intriguing
modern
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| |
theory suggests also that
some of this "primitive"
carbon may have come from
convection cells
transporting liquid metallic
C to the upper mantle from
the lower mantle-Meyer,
1985.)
By contrast, the carbon in eclogitic
(E-type) diamonds is thought to have been
transported to deep levels with the basalt
of the sub ducted sea-floor plates, such that
when the basalt turned to eclogite, the
carbon turned to diamonds and after it is
crafted into a great diamond
engagement ring. In this case, the
sources of carbon might have included both
carbonaceous crustal sediments (e.g.
limestones from geosynclinal trenches) and
organic remains on the ancient seafloors.
The differences between the carbon of P-type
and E-type diamonds correlate well with the
derived ages of diamonds of the two types.
all P-type diamonds have been found to be
very old, at least 3 billion years, whereas
some E-type crystals are well under 1
billion years old-suggesting that E-type
diamonds may be the byproducts of different
tectonic cycles of differing ages. (These
age-dates for the diamonds themselves are
not to be confused, of course, with the
dates of intrusion of the kimberlite pipes,
which range, for known pipes, between 1,600
and 50 million years ago). |

Diamond engagement ring |
|
|
Since the discovery of the first African
kimberlites, the worldwide hunt for more
such structures has revealed a definite
pattern of distribution: kimberlite and
lamproite diatremes are almost always found
within the innermost, stable parts of
continental shields-the original and most
ancient, cratonic nuclei of continents. P-type diamonds repose
in the cooler thermal "keel" of very old
upper-mantle peridotite under the craton,
wherein they formed during very early times.
E-type diamonds occur in the eclogite below
this keel, which has been sub ducted
(originally as sea-floor basalt), perhaps at
a much later time. A kimberlite diatreme
such as Kl on the diagram, having passed
through both regions, will contain diamonds
of both types, with those of the P-type
probably predominating. A diatreme such as
K2 will have "sampled" only the eclogite
region and thus will contain only E-type
diamonds. A diatreme, like K3, situated out
too far from the cratonic center, will have
"sampled" neither region and thus will be
barren of diamonds. Ll represents a
lamproite diatreme of the Argyle, Australia
type, situated near a cratonic margin and
containing both E-type and P-type diamonds,
perhaps because of a complex system of
interconnecting fractures at depth (Kirkley
et al.., 1991).
Although the general picture sketched above
would seem to account very well for the
great bulk of the world's diamonds, one
anomalous occurrence in New South Wales,
Australia has recently given rise to an
alternate model of diamond formation which
may sometimes apply. About two million
diamond crystals, with an aggregate weight
of about 500,000 carats, have been found in
alluvium in the Copeton-Bingara area, in
eastern New South Wales. Despite intensive
exploration, no kimberlite or lamproite
diatremes have been found in the area, and
the nearest cratonic block (west of Broken
Hill) is about 1,000 km away. If a
nearby source for the diamonds is
posited, another theory of their
formation and/or transport to the
surface is needed, and such a theory
was published in
|
1996 by Barron et al. These authors propose that the
diamond stones were formed in sub ducted oceanic
plates along the eastern margins of
Australia, at only about half the depth
thought typical for diamond formation in the subducted eclogites of the "standard" model
outlined above. When this oceanic crust
plunged under the continental plate, the
authors argue, it remained much cooler than
its surroundings; the combination of rapidly
increasing pressure and relatively low
temperature opened a "window" into the
stability field of diamond. Subduction then
stopped, preserving the diamonds which had
formed, and later these were transported to
the surface by non-kimberlitic magmas such
as leucitite, melilitite, nephelinite, and
basanite-"diamonds have been found in
several diatremes and dikes with these
compositions in eastern Australia" (Barron
et al, 1996). The authors correlate various
characteristics of the Copeton |

Diamond Stones |
|
diamonds-nitrogen content, color, carbon
isotopic composition and others-with several
rock types that presumably existed in the
original oceanic plates, and they propose
that, depending on the rock type, the carbon
was either of "primitive" origin or existed
as limestone or organic remains in trench
sediments. Some diamond formation, they
suggest, may even have been catalyzed by
natural fullerene carbon molecules. Once
formed, the diamonds rested in "cold
storage" in their static, partially
subducted rock slabs, whose temperatures
remained low, for up to 100 million years
before transport to the surface.
|
Obviously, the whole question of diamond
formation is still dynamically open, and
there are many remaining uncertainties even
in the "standard" picture. What, for
example, is the detailed nature of the
processes which accumulate carbon in the
primordial peridotites? How much of the
carbon in E-type diamonds is organic in
origin, and how young might the E-types
conceivably be? Why do kimberlite melts form
at depth, and what propels them so rapidly
to the surface? The sense of romance that
clings like an aura around diamonds arises
not only from their beauty, their gemstone
value, and their rich historical lore, but
also from the unsolved mysteries which still
persist in the shadowy, remote reaches of
deep-earth science.
Round diamonds, run for the
diamonds, Russian diamonds, sapphire
diamonds, sea of diamonds, sell
diamonds, Sierra Leone diamonds,
simulated diamonds, small diamonds, smitty diamonds, some days are
diamonds, south Africa diamonds,
synthetic diamonds,
All Brazilian diamonds were declared to be
the property of the Portuguese state, and
all diamond mining declared to be a Crown
monopoly. This simple
policy, based on simple state greed, ensured
that the industry would remain
static,without achieving major advances in
mining techniques or in economic development
of the diamond market. Mid-20th-century prospecting revealed
hundreds of kimberlite outcrops in Brazil,
but all mining during the period 1725-1865
took place in alluvial, eluvial or colluvial
deposits. Some lithified "bedrock alluvial"
sites were worked by benched quarries, and
matrix specimens of diamond crystals in
coarse
conglomerate were sometimes found.
Miners to this day may try to sell
visitors fake specimens of this
type, with the crystals glued onto
the matrix (Cassedanne,
1989). In the early days, mining was done by
slaves under the whips of the Portuguese.
After Brazilian independence there was much
freelance prospecting, and garimpeims often
formed co-operative organizations, the
miners sharing the work and dividing the
profits among themselves and with financial
backers, as well as with owners (if any) of
the lands hosting successful prospects.
Diamond fields speckle most of the southern
half of the country, but the richest sites,
and the earliest found, stretch along the Jequitinhonha River for many tens of
kilometers north of the town of Tejuco (Diamantina).
Diamonds there are found in gupiaras (coluvial
terraces high above the streambeds),
gorgulho (eluvial plateau deposits), and
cascalho (gravel deposits in the streams).
In the cascalho deposits, the most important
type, gravels were (and are) washed and
sorted in complex systems of hoses, pumps,
sluices, and washing crates, while women and
children comb adjacent parts of the
drainages for diamonds. A mechanized
dredging operation in the Jequitinhonha
River, 80 km downstream from Diamantina, is
the only contemporary Brazilian diamond
"mine," producing 1 carat of diamond and 1
gram of gold for each 100 cubic meters of
gravel (Maillard, 1980; Cassedanne, f989).
The featured collection's only Brazilian
diamond is a typically frosty and somewhat
irregular crystal measuring 1.3 cm and
weighing a little over 11 carats. It comes
not from Diamantina, Minas Gerais, but from
"Estralla do Sol, Mato Grosso." The province
of Mato Grosso is in west-central Brazil,
bordering Goias Province on the east and
Bolivia and Paraguay on the west; its
capital is the town of Diamantino, near
which the chief diamond field of the
province is located. Prospecting for
diamonds (and gold) in this remote region
has never been as intense as in the other
fields to the east. According to Cassedanne
(1989), "A period of excitement and wealth
was short-lived, ending in 1847 with the
decline in gold production. In the year of
1852 the Mato Grosso Mining Society went
bankrupt [and] the Diamantino prospect was
abandoned."
In recent years, however, diamond mining
activity has picked up in the province. Near Diamantino and north of the city of Cuiaba,
a 63,000-hectare claim block now known as
the Mato Grosso Diamond Project was host to
a large-scale diamond rush in the 1960's,
when alluvial diamonds were first discovered
in the Morro Vermelho Formation. The
proliferation of high-quality diamonds being
found by prospectors in the area attracted
several major diamond mining companies, and
more than 50 kimberlite pipes were
discovered. Diamonds collected from the
property exhibit pristine or near-pristine
surfaces, suggesting a local source for the
significant number of alluvial diamonds
found on the claims. Eclogitic garnets have
also been found in two of the initial heavy
mineral samples collected. Iciena Ventures,
Inc. is part owner in the project, and
recently announced the acquisition of 47
prime diamond exploration permits covering
438,000 hectares in the states of Mato
Grosso and Rondonia, Brazil (www.iciena.com).
An area in the southern tip of the state
of Rondonia and the northwestern part of
the state of Mato Grosso also has large
reserves of diamonds. Mining is forbidden
there because it is in the protected
homeland of the Cinta Larga Indigenous
People; however, nearly 3000 garimpieros and
miners entered the area illegally to mine
diamonds in 1999, and eventually had to be
evicted by government troops. The Federal
Police estimates that gems amounting to 50
million dollars were smuggled from the
region to Belgium last year.
In the juina Diamond Province, Mato
Grosso, the Diagem International
Resources Corporation currently has 130,000
hectares of mineral claims. The Province has
vast deposits of alluvial diamonds as well
as 7 identified diamondiferous kimberlite
pipes on which basic exploration is
complete. Over 130,000 carats of diamonds
were recovered during the evaluation phase,
including large stones up to 450 carats, and
a 100-carat pink crystal. Production began
in 1996 (www.diagem.com).
- Argyle mine, Western Australia, Australia
No diamonds from Australia reached the world
market until 1981, but by 1995 the country
had assumed first place in annual diamond
production worldwide. Most of this
ballooning output has come from the Argyle
mine, in the East Kimberley diamond
province, situated in the northeastern part
of Western Australia. The workings consist
of a huge open-pit mine in a lamproite pipe.
It is somehow satisfying, though merely
coincidental, that this Australian
"Kimberley" region was named (in 1880) after
the same Earl of Kimberley, then British
secretary of State for the Colonies, after
whom the great De Beers New Rush diamond
mine in South Africa had been renamed the
Kimberley mine in 1873 (Grice and Boxer,
1990).
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Pink Diamond from the Argyle-Mine Australia |

Pink
Diamond from the Argyle-Mine
Australia very clear |
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Diamond from the Argyle-Mine
Australia |
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What have Victoria
Beckham, Jennifer Lopez and other
celebrity in common ?
They own some diamonds from the
Argyle-Mine in Australia. Pink
diamonds from the Argyle-Mine fetch
around 10 times the price like a
"ordinary" white diamond of similar
quality and size. The diamond right
above costs as much as a nice fully
equipped Rolls Royce. The Argyle-Mine in
Australia is operated by Rio Tinto Diamonds. This diamonds of a
very rare and beautiful red color
are almost only to be found in the
Argyle-Mine.
It looks like
somewhere around 2018 the mine will
dry up, that means this kind of
diamonds have a bright future in
terms of prices.
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Australian
diamonds were first found in New South Wales
in 1851, in alluvium being washed for gold,
and New South Wales produced modest
quantities of diamonds for a few decades
thereafter. In Western Australia, although a
few alluvial diamonds were found near Nullagine in 1895, major prospecting did not
begin until the late 1960's. A few
kimberlites and a few diamond-bearing
alluvial deposits were found in the
Ellendale and Noonkanbah areas in the early
1970's, but the real bonanza followed the
discovery, in 1979, that Smoke Creek was
full of diamonds. Prospectors following an
easy trail of these alluvial deposits
upstream for about 20 km came to the primary
source-the Argyle (AKl) lamproite pipe.
This was only the second (Murfreesboro was
the first) primary diamond deposit found
anywhere in any rock other than kimberlite-and
there are now known to be at least 100 other lamproites in the Kimberley area, many of
which contain diamonds (Harlow, 1998).
Though similar in its origins to kimberlite,
lamproite is finer-grained and
lighter-colored (typically it is gray to
greenish gray, and mottled), and differs
somewhat in its mineralogy. The major
component species are forsterite, phlogopite,
diopside, richterite, chromite and pyrite,
and some of the lamproites of the Kimberley
area also contain some very rare species,
including priderite, jeppeite and wadeite
(Grice and Boxer, 1990). However, diamonds
from lamproites do not seem to differ in any
important way from those found in
kimberlites. Argyle mine diamonds show a
wide range of crystal forms, colors and
twinning habits, but such a range is also
commonly seen in kimberlite diamonds.
Argyle mine crystals average only 0.1 carat
in weight. The largest found up to 1998
weighs 41.7 carats. Only about 5% of the
crystals are of gem quality. In 1995 the
mine produced 38% of the world's diamonds as
measured by weight, but just 6% as measured
by value (Harlow, 1998). About 75% of the
stones have dark inclusions, rendering them
brown, yellow, or (in cases of larger, "bort"
diamonds) steel-gray. However, a few rare
stones are green or colorless, and pale pink
ones are something of a specialty of the
mine, making lovely and very valuable gems
(see a dramatic photograph of a swarm of
pink crystals in Grice and Boxer, 1990). The
Argyle diamond crystals in the collection
featured here are a lovely, gemmy brown,
1.1-cm octahedron weighing about 4.4 carats,
and a smaller but sharper, purplish brown
octahedron measuring 6 mm.
Production at the Argyle mine began to
fall off in 1999, and the deposit is
expected to be largely exhausted, and the
mine to close, by 2006. However, Ashton
Mining, the company which operates the mine,
should recoup any loss of income, as it is
also 100% owner of Australia's only other
hard-rock diamond operation, at Merlin in
the Northern Territory. This mine, which
began production in 2000, exploits a number
of small kimberlite pipes with much higher
gem-quality diamond content than Argyle's,
and it is expected to remain productive for
a long time to come (www .mbendi.co.za).
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- Orapa mine and Letlhakane mine, Botswana
Between 1967 and 1973,
DeBeers geologists
located three richly diamondiferous kimberlite pipes in Botswana (formerly
British Bechuanaland), with the eventual
result that this poor, under populated nation
in the Kalahari Desert (and right over the
center of the Kalahari Craton) is now third
in the world in diamond production as
measured by carat weight, behind only Zaire
and Australia. Moreover, since there is a
very high ratio of gem-quality to industrial
quality diamonds here, Botswana since the
early 1990's has led the world in diamond
production as measured by value. Many
kimberlites occur in the country besides the
main three (Orapa, Letlhakane, Jwaneng), and
many smaller mines are now working. Nearly
all diamond production is controlled by the
Debswana Diamond Company, a joint venture
firm of which 50% is owned by De Beers and
50% by the government of Botswana (www.
mbendi. co. za).
The Orapa kimberlite pipe, discovered in
1967, is exploited by the second largest
pipe mine in the world, surpassed in size
only by the Williamson mine in Tanzania
(Webster, 1983). The outcrop of the Orapa
pipe-the only known kimberlite pipe in
Botswana not overlain by sand-covers 263
acres; production commenced in 1970 (Harlow,
1998) or 1971 (Webster, 1983). The Orapa
kimberlite is remarkably well preserved,
having suffered less erosion than any other
known major kimberlite pipe. Only the
topmost few meters are missing, and the
great bulk of the diatreme remains intact
and awaiting exploitation (Kirkley et al.,
1991). As of 2000, after a major expansion
of the open-pit mine, the Debswana Diamond
Company planned to shift to an underground
operation, working through twin vertical
shafts to reach the lower sections of the
kimberlite. The life expectancy of the mine
has been estimated at another 30 years (www.mbendi.co.za).
Orapa mine diamonds, most
of them in various shades of yellow, but
also including two large multiple-crystal
clusters to 2.2 cm and two lovely, gemmy
pink crystals to 5 mm (one of them a
tetrahexahedron). Several of the yellow
crystals show cubic penetration twins, and
two have an odd skeletal habit that is
probably the result of twinning. Near the town of Letlhakane, 48 km
northwest of the Orapa pipe, two smaller
pipes, Letlhakane 1 and Letlhakane 2, were
discovered in 1968. The mines here came into
production in 1976; nearly 40% of the
diamonds found in them are of gem quality
(Webster, 1983). The specimen shown here is
a very gemmy, faintly yellow, 1.6-cm crystal
weighing about 12.6 carats.
The third and greatest
of the
diamondiferous kimberlite pipes in Botswana
(not represented in the collection featured
here) is the Jwaneng, much farther south
than the Orapa and Letlhakane. This is the
second most productive single diamond mine
in the world, after the Argyle mine in
Australia, in terms of carat-weight, and the
world's most productive in terms of value
(since, again, the percentage of gem
crystals is very high). The pipe is hidden
under 165 feet of sand; its discovery in
1973 was the result of a rigorous search
program directed by Dr. Gavin Lamont of De
Beers (Maillard, 1980).
|
- Kimberley district, Cape Province,
Republic of South Africa
"Kimberley district" is unfortunately a
vague term for the purposes of a label,
since several kimberlite pipes near the town
of Kimberley have produced diamonds in huge
numbers-not to speak of the comparably huge
numbers of alluvial diamonds found in the
area before (and since) their primary
sources became known. This is certainly the
most famous of all the world's diamond
regions, whose history has been written in
many places. Offered here are only a few
points of "color"; for a really full story
told by an upclose observer/participant, see
Gardner F. Williams' The Diamond Mines of
South Africa (1905).
The history begins in late 1866 or early
1867, when some children of a Boer
(Dutch-descended) farming family named
Jacobs found a transparent, 21-carat diamond
on the south bank of the Orange River-some
say that the finder specifically was
15year-old Erasmus Jacobs, others favor a
daughter named Fredrika, and other
candidates for the honor also exist (Janse,
1995). Mrs. Jacobs showed the pretty stone
to a neighbor named Schalk van Niekerk,
telling him that if he liked it he could
keep it; she was accustomed to seeing piles
of such pretty stones (only smaller) that
the children built in the fields. After
several more casual changes of hands the
plaything ended up with Lorenzo Boyes, who
was either acting Civil Commissioner of the
British Cape Colony (Williams, 1905) or the
town clerk of Colesberg (Janse, 1995), and
Boyes, having the stone tested, found that
his suspicion had been correct: it was a
diamond. Frenzied rushes of diggers to the
gravel beds of the Orange and nearby Vaal
Rivers followed (see later), and then came
the rushes to nearby "dry digging" sites,
where diamonds were being picked from loose
deposits of yellow, calcareous dry mud on
farmers' lands.
At first, and despite the dryness and heat
of the work sites, this mud-"yellow
ground"-in which the diamonds occurred was
thought to be some kind of water-deposited
sediment; after all, the searchers had just
recently been finding alluvial diamonds in
riverbeds. When, at some sites, they neared
the bottom of the dry, yellow mud, revealing
a hard bluish-gray rock beneath, some
diggers gave up and sold their claims,
believing that the diamondiferous ore had
run out. But those optimists who kept
working, hacking into the "blue ground,"
were delighted to find that diamonds
continued to appear. Noting how easily the
mysterious rock weathered, they broke it up
and spread it out in the sun in wide
"floors," so that after six months or so it
would turn, in effect, to yellow ground
which could be sieved to recover the
diamonds (Janse, 1995). In 1872 the German
mineralogist Emil Cohen became the first to
propose that the dark cylindrical columns of
rock, as uncovered below the weathered zone,
were in fact volcanic pipes. During the rest
of the decade the idea that diamonds come
from these igneous pipes won general assent,
and in 1887 the American mineralogist Henry
Carvill Lewis proposed the name kimberlite
for the rock.
| |
By this time the great diamond mines in the
blue ground had already been initiated in
quick succession. Maybe to find some blue
diamonds. Four of the deposits fall
within a circle 5 km in diameter, which
includes also the city of Kimberley. In
order of their discovery they are Bultfontein (September 1869), Dutoitspan
(October 1869), De Beers Old Rush, later
simply De Beers (May 1871), and De Beers New
Rush, later Kimberley (July 1871). Two more
pipes, Koffiefontein and Jagersfontein, lie
90 and 150 km respectively to the southeast.
In 1890 another huge pipe, Wesselton, was
found only 3 km from Bultfontein and
Dutoitspan.
The De Beers mine was begun on a farm,
called Vooruitzigt, owned by two Boers, the
De Beers brothers. They sold the land for a
sum that anyone more sophisticated would
have thought negligible, then couldn't think
what to do with the windfall except perhaps
buy a new wagon and some ox yokes (Krajick,
2001). But, because the mine named after
them ultimately became so famous, their name
eventually became attached to the great
diamond cartel called De Beers, still one of
the wealthiest and most powerful business
concerns in the world.
As already mentioned, the first Kimberley
diamonds were found in the loose yellow
earth of shallow "pans," as
dry ponds were called by the Boers- |

Blue
Diamonds |
| |
Dutoitspan" literally
is the "pan" on the land of a farmer named
Du Toit. The news of these thrilling new
kinds of diamond fields reached the alluvial
diamond-digging communities on the Orange
and Vaal rivers very quickly, of course; and
soon the taciturn, pious Boers who owned and
farmed the lands found themselves
overwhelmed by fame, although, for the most
part, not by any instant wealth. Makeshift
leasing and royalty arrangements were
insufficient to cope with the numbers of
people and volumes of potential profit
involved, and the Boer government of the
new, tiny, precarious Orange Free State was
out of its depth. It tried to restrict the
allotment of claims on the farm lands to all
but citizens of the Free State, but since
the claimants in reality came from every
part of the world and every moral terrain of
the soul, the Free State government soon
lapsed into passivity. Besides, the regional politics were
complicated and tricky. Some indigenous
tribes still asserted a vague kind of claim
to some of the diamondiferous lands. The
Orange Free State, of course, also asserted
a claim; and in Cape town there was the
increasingly aggressive authority of the
British Cape Colony under its new High
Commissioner, Sir Henry Barkly. In 1871 Sir
Henry concluded an arrangement, subject to
(routine) ratification by Her Majesty's
government, for the transfer to Great
Britain of the claims of the native African
chiefs. After some legal maneuvers which had
the effect of locking out all claims of the
Orange Free State, British sovereignty over
the new Crown Colony of Griqualand West,
which included the diamond fields, was
proclaimed
|
The imperial gesture probably
helped ensure that the diamond fields would
be exploited with maximum profitability, and
was in any case surely in tune with the
times. A voice clearly speaking from the
mind-set of those times (that of G.
Williams, 1905) rhapsodizes that ". . . this
settlement was greatly contributory to the
extraordinary advance of diamond mining ...
as well as to the uplifting and development
of the Colonies, and to the push of
civilization into the heart of the dark
continent."
No one better personifies this Imperial
spirit than Cecil John Rhodes, who, in
the rhetoric of Williams (1905) again,
sought "to reach ends of Imperial scope, to
throw the searchlights of civilization into
every cranny of the Dark Continent, to lift
the prodigious dead weight of unnumbered
bygone ages of barbarism ... to create a
|

Diamond mining at Zimbabwe |
|
Greater Britain ... and
stretch the hand of his
Queen over a realm transcending the farthest
sweep of the Macedonian or the Roman." By
the time of his death in 1902, Rhodes indeed
had done more than anyone else to make
southern Africa British, as far north as
Kenya and Uganda-working from a power base
secured by diamonds and by his mighty
creation, the De Beers corporation. |
|
When Rhodes came to Africa in 1870 to
seek diamonds, he was merely the sickly
17-year-old son of a Hertfordshire
clergyman. It was his ambition, imagination,
and financial daring which finally gave him
the victory, after years of capitalistic
battle, over another ambitious adventurer, a
Jewish shopkeeper from London named Barnett
Isaacs, also known as "Barney Barnato."
Barnato had come to work as a "kopje
wallower" (amateur diamond buyer) in the
Great White Camps of the diamond fields in
1873, joining his older brother Henry. With
an equally inexperienced partner, Louis
Cohen, Barnato soon began buying up claims,
and founded a diamond company-thus moving
into direct competition with Rhodes, who was
doing the same sort of thing. The two
entrepeneurs' rivalry did not end until
1887, when Rhodes bought out Barnato and
incorporated their combined holdings as the
De Beers Consolidated Mines Limited. Rhodes'
other great creation, the British African
Empire, is now gone, but the De Beers cartel
is supreme to this day in the (now
worldwide) diamond trade.
One dramatic episode in the early history
of Kimberley deserves mention. In 1899
the Boer War broke out, itself a perfect
artifact of British imperialism, as the
British victory ended all Boer, not to speak
of native African, aspirations to
independence. Between October 1899 and
February 1900 the Kimberley mine, and
Kimberley town, came under military siege.
An ill-organized but well-armed force of
angry Boers surrounded the town/mine complex
and bombarded it with long-range artillery;
fortifications around the town and mine were
erected, and small engagements were fought
between British patrols and the besieging
forces. In advance of the siege Rhodes had
sent from Capetown a small but stout British
force and ample supplies; food was rationed
during the siege, and some diamond mining
even continued. During one period of
especially fierce bombardment, several
hundred women and children took refuge for
several days in the mine's deep tunnels. By
the time a British relief column finally
arrived, nine people had been killed in
Kimberley, and many houses destroyed, but
the brave defense had solidified local
pride, and no permanent damage had been done
to the mine.
In 1914 the Kimberley mine closed, having
been worked to a depth of 1,098 meters; its
site is presently marked by the famous "Big
Hole," the deepest manmade excavation on
earth. Four of the giant original mines are
still active today: Bultfontein, Dutoitspan,
Wesselton and Koffiefontein. Their combined
production during the 1990's averaged only
about 700,000 carats of diamonds annually,
accounting for 0.7% of world production. The
mines are close to the bottoms of their
reserves of kimberlite ore, and all may be
closed permanently by 2010 (Harlow, 1998).
The Kimberley diamond crystal illustrated
here is a very gemmy, interestingly modified
1.4-cm octahedron weighing 11.3 carats.
- Premier mine, Transvaal, Republic of
South Africa
Up until 1903 the diamond mines around Kimberley had
supplied all of South Africa's (and the
world's) kimberlite diamonds. But in that
year a large
|
|
diamondiferous pipe 20 miles from
Pretoria, in the province of
Transvaal, went into production as
the Premier mine. Diamonds had been
found abundantly in the soil there,
especially around the Elandsfontein farm, as far back as 1897, but
apparently some South Africans were
reluctant to think that this new kimberlite
deposit could possibly rival the already
world-famous mines at Kimberley, almost 500
km to the southwest. In an official report
in june, 1903-after the "Cullinan" diamond
had been found in the Premier mine-a mining
engineer employed by the Transvaal
government noted that although the soil of
this region was indeed full of diamonds, the
blue ground below would probably prove
unprofitable; others in the Transvaal Bureau
of Mines shared this view (Williams, 1932).
But according to a report issued on October
31, 1903 by the Premier Diamond Mining
Company, the Premier mine had already
produced almost 100,000 carats of diamonds,
valued at £137,435, during the first few
months of its start-up year. Ten years later
the company reported that the Premier mine
had yielded 2,107,983 carats of diamonds
worth £2,336,828 in the year ending October
31, 1913 (Williams, 1932). The mine achieved its highest average annual
production of diamonds during the 11-year
period between its opening and the temporary
suspension of mining at the outbreak of
World War I in 1914. Work resumed in 1917,
and by 1932, when the open pit had reached a
depth of 610 feet, there was still almost no
decrease in the diameter of the kimberlite
pipe (Williams, 1932). But soon thereafter
the miners encountered a sill of gabhro
intersecting the pipe (Bancroft, 1984), and
because of this barren ground the old
open-pit Premier mine closed in 1936. In
1946 it re-opened, this time as an
underground mine exploiting kimberlite below
the gabbro, and as of today, one year past
the mine's centennial, diamond production
still continues. The deposit enjoys record
longevity in another sense too: it is
geologically the oldest of the major known
kimberlite intrusions, dating between 1,100
and 1,200 million years (Bancroft, 1984;
Kirkley et al., 1991).
On the popular level, the story of the
Premier diamond mine is the story of Thomas Cullinan,
and of the "Cullinan" diamond. Thomas
Cullinan, born in the British Cape Colony,
inherited a prosperous
construction business, but
before the turn of the 20th
century he sold off most of
his assets and moved north,
into the Witwatersrand area
near Johannesburg,
Transvaal, where he devoted
himself to prospecting for
diamonds. Knowing that they occurred in the soil near
the farm called Elandsfontein, he offered to
buy the farm from its owner, Joachim
Prinsloo, who responded by threatening to
shoot Cullinan and any other prospectors who
might trespass on his land.
The Boer War put
a halt to most prospecting anyway, and Prinsloo died before the war ended. In
November 1902, the persistent Cullinan was
finally able to purchase the farm from the Prinsloo heirs for £52,000. In January 1903, diamondiferous kimberlite
began to show up in the prospect pits, and a
De Beers geologist came for a look.
Apparently sharing the general skepticism
about the viability of any kimberlites
outside of Kimberley, he reported to his
superiors that this new mine would be "a
flash in the pan" (Janse, 1995). On Janauary
25, a gigantic diamond was found less than a
meter below the surface, and mine manager
Frederick Wells dug it out of the ground
with his penknife (Bancroft, 1984). It was,
of course, the fist-sized, 3,106-carat "Cullinan"
diamond, by far the largest gemquality
diamond ever found anywhere in the world.
Bancroft (1984) tantalizingly points out
that the overall shape of the "Cullinan"
indicates that it was actually the smaller
half of an enormous, cleaved octahedron, and
somewhere the still-buried larger half of
the same crystal must certainly still exist.
The Cullinan
diamond was presented to
King Edward VII, and of the 105 separate
gemstones cut from it, the largest two, the
Great Star of Africa and the Lesser Star of
Africa, at 530.2 and 317.4 carats
respectively, are the largest faceted
diamond gems in the world. Today they are
seen by the thousands of tourists who visit
the display of the British Crown Jewels in
the Tower of London each week. As the diamond production figures cited earlier
show, the Premier mine during its
amazing first years provided
strong competition for the
mines of the De Beers
monopoly at Kimberley. De
Beers, moving quickly to rectify its earlier error
in judgment, reached an
"understanding" with the
board of directors of Thomas Cullinan's Premier
Diamond Mining Company in 1920, and by 1922
De Beers had acquired all shares in the
Premier mine (Janse, 1995).Cullinan was
knighted by Edward VII, and went on to a
successful career as a South African
politician; he died in Johannesburg in 1936. The four Premier mine diamond crystals illustrated
here include a gemmy, modified, 9-mm
octahedron, an interesting pair of gemmy and
colorless octahedral crystals attached to
each other in parallel, a 1.3-cm octahedron
darkened by many blackish inclusions, and an
extraordinary 1.3-cm crystal cluster
consisting of at least seven gemmy,
octahedral individuals growing on a matrix
lump of opaque diamond "bort."
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|
-
Vaal River district, Cape Province,
Republic of South Africa
The Vaal River, rich in alluvial diamonds,
passes through the "Kimberley district" of kimberlite-pipe mines (see above); in fact,
a bend of the river passes within two km of
the Kimberley mine. This description,
therefore, is to some extent redundant with
the description of the Kimberley district,
inasmuch as the diamonds have a common
source. The part of the Vaal River which has
historically been most productive of
diamonds runs northeast for about 150 km,
from Pniel and Kimberley to the town of
Bloemhof-although the very first finds came
from points farther south. About 100 km
southwest of Kimberley, just below the point
at which the Vaal River joins the Orange,
lies the site of the De Kalk farm, where in
1867 the Jacobs children found the large
crystal that started the whole South African
diamond excitement; in 1869 the 83.5-carat
"Star of South Africa" was found on the
Zandfontein farm, also very near the
junction of the Orange and the Vaal. After
some early prospecting in this area, though,
the early diggers moved north, to Pniel on
the Vaal, developing extensive diggings at a
place called Klipdrift, later Barkly West,
where the gravel beds yielded many of the
finest South African diamonds ever found
(Williams, 1932).
As early as 1869, about 4000 diggers were at
work in the Vaal and Orange Rivers (Webster,
1983). The swarming tent camps took in "a
motley throng of fortune-hunters" (Williams,
1905) from the neighboring Boer lands, from
the British Cape Colony, from other parts of
Africa, and from abroad:
Black grandsons of Guinea coast slaves and
natives of every dusky shade . . . butchers,
bakers, sailors, tailors, lawyers,
blacksmiths, doctors, carpenters, clerks,
gamblers, sextons, laborers, loafers . . .
fell into line in a straggling procession to
the Diamond Fields. Army officers begged
furloughs to join the motley troop,
schoolboys ran away from school, and women
even of good families could not be held back
from joining their husbands and brothers in
the long and wearisome journey to the banks
of the Vaal (Williams, 1905).
Soon, of course, the kimberlite mines
overshadowed the alluvial workings, but the
latter continued in action nevertheless,
being concentrated at points progressively
farther upstream on the Vaal, i.e. to the
northeast. In 1926, enormous alluvial
deposits were found in high plateau country
near Lichtenburg, 175 km north of Bloemhof,
and 10,000 prospectors joined a first rush
(Harlow, 1998). In the next year there was
an "organized" rush near Grasfontein in the
Lichtenburg field. A Transvaal government
official standing up on a cart proclaimed
the opening of a farm tract for digging, and
at the drop of a flag 25,000 people rushed
forward to plant their claims. The output of
alluvial diamonds from the Vaal River region
kept increasing well into the 20th century,
with a new surge from the Lichtenberg fields
after 1926, and production continues today.
From the start, Vaal River diamonds
enjoyed a reputation for being unusually
clear, bright, and free of fractures. Some
are lightly tinged yellow, and deep orange,
pale blue, brown and pink hues are found
very rarely, but a large percentage of the
stones are perfectly white. The commonest
crystal forms are the octahedron and
dodecahedron (Williams, 1905) The crystals
illustrated here (a beautifully gemmy, near
colorless 1.4-cm octahedron weighing 12.5
carats, and a 1.8-cm macle weighing 13.2
carats), having no doubt been found rather
recently, are probably from the northern
part of the Kimberley district, since, as
mentioned, the general historical trend was
that the alluvial workings moved
northeastwards along the Vaal from the old
Barkly West area near Pniel.
- Finsch mine, Orange Free State, Republic
of South Africa
The Orange Free State, briefly an autonomous
Boer state just before the turn of the 20th
century, is now a province of the Republic
of South Africa. The kimberlite pipe
exploited by the Finsch mine was discovered
in 1960. The mine, located on the Brits Farm
near Limeacre, 160 km west of Kimberley, is
a major producer of gem crystals-about 25%
of its diamonds are of gem quality (Webster,
1983). The discoverers of the pipe, Allster
Fincham and Ernest Schwabel, had been
working a claim there for asbestos, but when
they found garnets in the soil they
suspected the presence of underlying
kimberlite (pyrope being a major "indicator"
mineral). When the relevant mining law
changed in their favor in 1960, they began
mining diamonds. In 1963 the entire capital of the Finsch
Diamonds Company was purchased by De Beers,
and two years later the mine began fullscale
production. As a large open-pit mine with
many benches, the Finsch produced 95,000
carats of diamonds in 1965, with production
steadily increasing to 3,500,000 carats in
1985 (Maillard, 1980). The pit had reached a
depth of 430 meters before underground
mining commenced (Harlow 1998), and
ultramodern blockcaving methods of gathering
kimberlite ensure the continued importance
of the Finsch mine today.
The diamond collection illustrated here features a
superb suite of 13 Finsch mine diamonds in a
gorgeous array of colors including
canary-yellow, orange, pink, reddish brown,
colorless and black. The habits range from
modified cubic to octahedral to triangular
macle twins up to 6 mm in size. |
- Williamson mine, Mwadui, Tanzania
The Williamson mine is the largest
kimberlite mine in Africa, with a main pipe
eight times larger than that of the Premier
mine. It has yielded diamond crystals to 240
carats; a gorgeous pink 54carat stone was
cut to a gem of 23.6 carats and presented to
Princess (now Queen) Elizabeth on the
occasion of her marriage in 1947. Mwadui village lies in an area of
diamondiferous gravels between Shinyanga and
the southern shore of Lake Victoria; some
claims were pegged as early as 1910, and
limited mining began in 1925 (Webster, 1983; Janse, 1996). In 1934, Dr. John Williamson,
a geologist from Quebec, came to prospect in
Tanzania (then British Tanganyika), and one
of the last star-stories about an individual
diamond entrepeneur commenced: "Every
geologist dreams of discovering an important
diamond mine," wrote G. J. Du Toit in an
unpublished manuscript called The Williamson
Story, "[and] everybody wants to own one
outright. Only one man, Dr. John Thorburn
Williamson . . . the discoverer and founder
of the now-famous Mwadui diamond mine . . .
has ever achieved both ambitions" (quoted in
Maillard, 1980).
In 1940 Williamson had worked in three
small, unprofitable diamond mines in
Tanganyika, and had discovered a few small kimberlite pipes, but was nonetheless down
to his last £100 and thinking of joining the
army. But on the evening of March 6, 1940,
his assistant brought him a soil sample from
an abandoned survey trench near Mwadui;
processing it, the two men found not only
abundant grains of the indicator mineral
ilmenite but also a beautiful 2-carat
diamond octahedron (other versions of the
discovery-story exist, as we might expect-
see Janse, 1996). Soon Williamson's
systematic work at the site had revealed a
massive kimberlite pipe and associated
diamondiferous gravels, and the Williamson
mine was born. he was able to bootstrap the
mine's growth from profits, and built a huge
processing plant, a power station, and a
township for several thousand employees.
After Williamson's death in 1956, his heirs
sold the mine to De Beers, and continued
economic success followed Tanzanian
independence in 1961, and the mine's
nationalization (Maillard, 1980). According to the present owner, Tan Range
Exploration Corporation, the Williamson
diamond mine
is still operating, but on a much smaller
scale than previously. Through various
modern exploration technologies, e.g.
airborne magnetic-anomaly surveys, the
company has identified several new, although
small, kimberlite pipes in the area and
elsewhere in Tanzania. These might be
expected to compensate, at least partially,
for the expected closing of the Williamson
mine sometime in the fairly near future (www.tanzam
2000.com).
- Kenema, Diamond Fields, Eastern Province, Sierra Leone
The diamond fields of Sierra Leone lie in
hilly terrain north of the town of Kenema.
Bounded on the west by the Sewa River and on
the east by the borders of Liberia and
Guinea, the region measures about 80 × 100
km and accounts for about one-third of the
total land area of the tiny country.
Alluvial diamonds were first found in
Gboboro Stream in January 1930 by N. R.
Junner and J. D. Pollett of the Sierra Leone
Geological Survey (Janse, 1996), and there
was small-scale prospecting and mining until
the end of British colonial rule in 1961. A
company called Consolidated African
Selection Trust (CAST), through its wholly
owned subsidiary Sierra Leone Selection
Trust (SLST), acquired a diamond prospecting
lease over the whole country, and annual
production reached one million carats by
1937 (Janse, 1996). Even during this period,
as a harbinger of the chaos to come, more
diamonds probably left the country illicitly
than were sold by the mining company
(Webster, 1983). Sierra Leone diamonds are all
alluvial, being found by time-honored methods
of scouring and processing gravels in the
Sewa, Gboboro, Male and other small rivers,
and mining on terraces along these rivers.
This is a deeply weathered terrain, with
coarse-grained granite rocks underlying the
valleys and more resistant schists forming
the uplands, all overlain by thick soil
cover and dense vegetation. The remnants of
the original kimberlite pipes crop out in
only a few spots, now showing only their
once deepseated roots. They must once have
been large and richly diamondiferous, for
even after most of the diamonds have washed
out to sea, rieh alluvial deposits,
including many on high banks and ledges
which represent ancient drainages, are still
widespread.
Quite early on in the region's history,
Sierra Leone diamonds acquired the
reputation for being of highest gem quality
at their best, as well as very well
crystallized. Many crystals, called
"glasses," are sharp, lustrous octahedrons
of pellucid transparency, colorless in most
cases but rarely also bottle-green.
The "Star of Sierra Leone," found at Yengema in
1972 and weighing 969.8 carats, is the
largest alluvial diamond of gem quality ever
discovered anywhere. During the last years of British rule the
villagers of the region, having learned
about how to find diamonds and about their
extremely high value, began illicitly
collecting and selling them on a large
scale, with fortune-seekers from neighboring
Guinea and Liberia often joining in too.
These are among Africa's poorest
countries-Sierra Leone is the poorest-so the
diamond mania was not surprising, but it
soon threatened the overall economy of the
colony. "Farmers neglected their crops and
livestock to such an extent that the
government had to import commodities like
rice, which in normal times Sierra Leone
exported. Instead of enriching the country,
diamonds were threatening to ruin it. In the
region of the diggings there was a severe
shortage of food, and prices rose to
dizzying heights" (Maillard, 1980).
The British, by issuing diamond-collecting
licenses and by encouraging the villagers to
dig for the official company SLST, attempted
to get control of the situation. But
large-scale illegal trading still went on,
especially after large numbers of Lebanese
merchants moved in to seize control of
smuggling activities close to the border of
Liberia, in whose capital, Monrovia, diamond
dealers and cutters from Antwerp and
elsewhere waited to buy smuggled gems at
very low prices. In 1955 the British, in co-operation with
DeBeers, countered by authorizing the
Diamond Corporation of Sierra Leone (DCSL)
to set up a buying office in Freetown, the
capital city, with smaller outposts in
villages near the sources. "Miners" then
could individually bring diamonds to sell at
fair prices, and without risk to themselves,
and the diamonds could be taxed by the
government, then channeled into established
international markets. The single SLST
concession for all of Sierra Leone was split
into two lease areas, called Yengema and
Tongo (Janse, 1996).
But since Sierra Leonean independence in
1961, and especially after the country
became a republic in 1971, the story of
diamonds there has been largely one of civil
war, mayhem, deepening poverty, cruelty, and
death-one of the world's worst and least
noticed "news" stories of recent decades. A
series of government coups and
counter-coups, these supported or undermined
variously by the governments of major powers
and by the forces on different sides of the
civil conflict going on in neighboring
Liberia, have cost tens of thousands of
Sierra Leonean lives. Government and rebel
forces have both typically formed their
armies from underfed children and from
alcohol and drug-addled young men, and all
sides have employed mercenaries from the
U.S., Russia and Europe to "lead" them. In
one rebel offensive against Freetown between
December 1998 and February 1999, at least
7,000 people died, and, in the overheated
(but not necessarily inaccurate) language of
one website, "Women and young girls were
raped systematically . . . The population
was routinely used as human shields. . . .
Entire compounds of families have been
emptied, the villagers lined up while the
rebels jokingly decide which ones to shoot
and which to let go . . ." (www.comebackalive.com).
Mutilations, especially the chopping-off of
arms and legs, have been practiced on a
large scale, foreigners have been executed,
villages have been starved, and reports of
cannibalism persist.
Clearly the most common motive for all this
violence is greed for the diamonds which are
Sierra Leone's only significant source of
wealth and accessible symbol of power. "The
diamond mines were the first targets for
repossession, as one of the would-be
dictators hired [mercenaries] on credit,
with a promise of US $500,000 a month
payment in diamonds" (www.comeback alive.com).
Such are the facts which lurk behind the
vaguely, often glibly used term "conflict
diamond"-one may or may not choose to bear
them in mind while contemplating the two
crystals illustrated here, a colorless,
modified 1.3-cm octahedron (with a smaller
"side-car crystal") weighing 7.5 carats, and
a colorless triangular 1.1-cm made weighing
4.6 carats.
Between 1960 and 1996, "official" diamond
production from Sierra Leone fell from 2
million to 400,000 carats per year; however,
in 1996 a Canadian company was thinking of
mining a small kimberlite pipe where
gem-quality diamonds seem to comprise an
extraordinary 60% of the total yield (Janse,
1996).
- Oranjemund district, Orange River,
Namibia
Oranjemund lies, as its name specifies, at
the mouth ("Mund") of the Orange River,
where this river empties into the South
Atlantic. Since the Orange River forms the
border between Namibia and the Republic of
South Africa, Oranjemund is at the
southernmost point of Namibia (formerly the
South African protectorate known as
South-West Africa, and before World War I
the German colony of Deutsch Sudwest Afrika).
At Oranjemund, the Namdeb Diamond
Corporation Limited (owned jointly by the
Namibian government and De Beers) maintains
a fleet of earth-moving equipment "nearly as
large as that owned by the United States
army" (Maillard, 1980), and uses it to
conduct a mammoth beachmining operation for
diamonds.
"Beach" diamonds were first detected
along this coast in 1908, near Luderitz,
where a railroad worker found a few small
crystals in the sand dunes. Soon, discrete
beach deposits were being found along a
60-mile stretch north of the mouth of the
Orange, and the Germans were mining
considerable numbers of small but
highquality diamonds. When South Africa took
control after World War I, the deposits were
sold to Consolidated Diamond Mines (CDM),
which was transferred to DeBeers in 1929;
the present Namdeb Corporation was organized
in 1994. Its current operations include
beach-mining, terrace-mining, and
seabed-mining-all flourishing nicely, and
imparting a new sense to the old term
"alluvial diamonds."
For a while geologists wondered whether
these marine diamonds had come from kimberlites on the sea floor, or whether
they had been transported oceanwards from
the great kimberlite swarms of the inland
Kalahari Craton. But it is now quite certain
that kimberlites do not occur in the ocean
basins, only in continental cratons, and
moreover a mere glance at a stream-drainage
map of southern Africa makes it clear that
huge numbers of diamonds from inland
kimberlites must have been transported to
the sea by the Orange River system
(including tributaries such as the Vaal);
further, it has been noted that the sizes of
the marine diamonds diminish regularly as
the distance from the mouth of the Orange
increases. Presently it is estimated that
over the past 100 million years, up to 1,400
meters have been eroded from the land
surface of South Africa and Namibia, and
that of all of the diamonds released to the
streams by the weathering of the kimberlites,
only 10% stayed behind in inland alluvial
deposits, the remaining 90% having been
carried to, and out into, the ocean. And
since the ocean waves shatter the
poorer-quality diamonds, 90-95% of marine
diamonds are of gem quality (www.amnh.org/exhibitions/diamonds).
Terrace mining for diamonds
at Oranjemund
takes place well above the high-water level
and up to 3 km inland, and seabed mining,
carried out by suction-dredging from huge
offshore barges, operates more than a mile
out from the mouth of the Orange. More
important than either of these is beach
mining. In the first stage of this process,
massive earth-moving equipment removes loose
beach-sand overburdens to depths of up to 80
feet, exposing ancient beach terraces as
much as 65 feet below present high-water
levels. The terraces are broken up and
bulldozed into rubble-piles until the tough,
irregularly configured bedrock schists are
laid bare: this is the level most avidly
sought, since the gravels left in the
potholes and crevices here have concentrated
most of the diamonds.
Backtrenchers with digging buckets gouge out
some of the gullies, but mining from this
point is largely a matter of hand work:
miners known as bedrock cleaners dig,
shovel, and sort the highly diamondiferous
residual gravels, until the whole schist
floor is swept clean (Maillard, 1980). The
technology is efficient, and potential
yields from the "Oranjemund district" are
vast-in 1995 alone, such beach deposits
produced 1,300,000 carats of diamond
crystals (www.amnh.org/exhibitions/diamonds).
Similar beach diamond deposits have been located in Namaqualand, South Africa, south of the
mouth of the Orange, as well as much farther
north, on the "Skeleton Coast" of Namibia
(Webster, 1983). It is most likely, however,
that the specimen illustrated here (a gemmy
triangular made twin 1.3 cm across, weighing
4.1 carats) came from somewhere not too far
north of Oranjemund-and that the working
from which it came has long since been
buried again by tide-borne sands.
- Bangui region, Central African Republic.
Although only a tiny fraction of the world's
diamonds comes from the Central African
Republic, diamonds are this poor, landlocked
former French colony's principal resource.
The colony (which is partially underlain by
a small craton), was once known as
Ubangi-Chari; it lies just north of Zaire,
the latter also known as the Congo Republic.
Neither state should be confused with the
former French Congo, now the People's
Republic of Congo, lying just to the west of
Zaire (devotees of dioptase will be familiar
with these confusions). The Ubangi (or
Oubangui) River marks the border between
Zaire and the Central African Republic, and
Bangui is a town on the river's north bank.
The "Bangui region" (source of the crystal
illustrated here, a 1-cm yellow cube
weighing 4.1 carats) corresponds to a
diamond-producing area between Bangui and
Berberati, in the southwestern part of the
country (Maillard, 1980; Webster, 1983).
Here, diamonds are recovered by clearing
heavy forest and jungle vegetation, then
removing a thick bed of topsoil to reach
diamond-bearing alluvial gravel; there is
also some mechanized dredging in beds of the
region's numerous rivers and streams.
Further diamond-related developments may
follow when the parent kimberlite or
lamproite pipes (if they still exist) are
finally located in the Central African
Republic.
- Northern Lunda Province, Cuango River
area, Angola
Angola produced 1.8% of the world's diamonds
in 1996 (www.amnh.org/exhibitions/diamonds),
and a high proportion are of gem quality.
Counterbalancing these upbeat observations,
though, is the fact that civil wars and
insurgencies have intermittently troubled
Angola ever since independence from Portugal
was declared in 1975. Consequently, as in
the case of Sierra Leone, diamonds known to
be from Angola may be "conflict diamonds."
At least half of all diamonds found in the
country are gathered and sold illicitly (Janse,
1996). Even when there is no fighting,
demobilized soldiers generally prefer to dig
gems rather than return to bare-subsistence
farming.
The Angolan diamond regions are all
in the northern part of Lunda Province, in
the country's northeastern corner, adjoining
Zaire,. In fact, the first discoveries of
alluvial diamonds, in 1911/ 1912, were
byproducts of exploratory surveys just to
the north, in what was then the Belgian
Congo. A series of parallel rivers run from
south to north through Lunda Province before
passing into Zaire, and diamonds have been
found in many of them. The Cuanga River,
forming the border between Lunda Province
and Malanje Province to its west, is the
largest of these rivers, and had produced
about 80% of Angola's diamonds as of 1998
(Harlow, 1998). It is possible, however,
that the stated source of the lovely 1-cm
yellow crystal illustrated here,"Cuango (or
Kwombo) River," is merely a geographically
convenient term, and that the diamond was
found in one of the region's smaller rivers
(candidates include the Chicapa, Luachimo,
Chiumbe, Luana and Lembe). Creative geological fieldwork by R. Delville
in the early 1950's succeeded in
establishing that diamondiferous gravels and
conglomerates were concentrated along two
parallel faults in a buried fault-graben
structure in Lunda Province, and inferences
could then be drawn concerning where the
original kimberlite sources lay concealed in
the forested wilderness of the province. The
first of the kimberlite pipes was found near
the Chicapa River in 1952; it is now known
to be one of the largest in the world (Maillard,
1980), and one of about 600 pipes in
northern Lunda (Harlow, 1998). Ongoing
mining and prospecting is in the hands of a
consortium, Consorcio Mineiro de Diamantes (Condiama),
whose members include De Beers, the
government of Angola, and an earlier company
called Diameng (Companhia de Diamantes do
Angola), which had begun to look for
diamonds during Portuguese colonial times.
- Ghana
Although Ghana is not represented by any of
the diamonds in the collection featured
here, it is the locality for the large and
amazingly modified cube shown on the cover
of this issue, from the collection of Mike
Scott. In 1911, British prospectors found
small numbers of alluvial diamonds in what
was then the colony called the Gold
Coast-more famous in history both for its
gold and for its infamous slave-trading
ports-on the Gulf of Guinea. As of 1980, 3
million carats of diamonds were being
produced annually, 85% of the output being
merely of industrial grade (Maillard, 1980).
In 1996 the country accounted for 0.7% of
world diamond production (www.amnh/exhibitions/diamonds). Alluvial diamond deposits in Ghana are
concentrated in the Birim valley, in the Akwatia region midway between the capital
city of Accra and the town of Kumasi (Maillard,
1980)-this is the likely provenance of the
cover crystal.
- The Future of Diamond Mining
Levinson et al. ( 1992) estimate that the
total world production of diamonds, both gem
and industrial, between remotest antiquity
and the year 1990 was 2,213,875,000 carats,
equivalent to 450 metric tons weight. This
is, they say, a conservative estimate, since
it rounds up only slightly from official
figures to take into account unreported,
illicit production. As mineral species go,
even gempotential species, diamond is not
really rare-how many tons of jeremejevite or
sinhalite do you suppose have been
found?-but its enduring appeal, not to speak
of its many industrial uses, makes the
securing of further supplies a pressing
concern.
Since 1870, Africa has spoiled us: in that
year, as mining was just beginning at
Kimberley and on the Vaal River, only
300,000 carats of diamonds were produced
worldwide, but in 1920, 3,000,000 carats
were produced, the tenfold increase being
entirely due to new production from African
sources. Although the classic African
kimberlite mines are now in decline (and
some are closed), new African mines, Russian
mines, and most recently the Argyle mine in
Australia have so far kept worldwide
production growing rapidly: 42,000,000
carats were produced in 1970, and more than
100,000,000 in 1990 (Levinson et al, 1992). But now several Russian mines, the
Williamson mine in Tanzania, and even the
Argyle mine are well past their primes-if we
keep up the present rate of consumption,
where are diamonds to come from in future
decades (aside from the vast stockpiles held
by the Russian Diamond Fund)? One plausible speculation is that more and
more of them will come from the sea. Marine
diamond mining off the Atlantic coasts of
South Africa and Namibia was pioneered by
two small companies in 1954. Then, in the
early 1960's, a Texas oilman named Sam
Collins founded a company called the Marine
Diamond Corporation, now in the capable,
high-tech hands of De Beers Marine (Pty)
Ltd. This company currently dominates the
available offshore lease areas, which extend
up to 5 km out from the shore (Gurney et al,
1991). There are several positive
indications about this diamond source: for
one thing, a conservative estimate of
reserves in the African marine deposits is
1.5 billion carats-almost three-quarters of
total world production since antiquity-and,
for another thing, 90-95% of the diamonds
are of gem quality, natural "sorting" having
destroyed the inferior stones along the way
between the original drainages of the kimberlites and final deposition on the
continental shelf.
To put it in terms of
another statistic, these diamonds deposits contain at
least 100 times as many gem diamonds (by
weight) as are presently being used each
year in jewelry (Levinson, et al, 1992).
However, diamonds recovered by relatively
simple suction equipment, and by divers, in
shallower waters are vastly outnumbered by
deeper-water diamonds, and these are
difficult and expensive to find and
retrieve. Much technical progress is being
made, but deep-marine diamond mining is
still only marginally profitable. It may
also be true that the South African/
Namibian marine diamond deposits are an
anomaly in the world, since they result from
the uniquely favorable combination of a rich
inland diamondiferous craton, deep
weathering of the craton, and stable
drainage over a very long time to a nearby
ocean. Prospectors have eyed the Arctic
waters north of the Siberian and Canadian
cratons, and some sites in the Gulf of
Guinea, but climatic as well as geological
factors would seem to preclude mining in
these areas, even if they should prove to
hold diamonds.
Although they acknowledge the importance of
the southern African marine fields, and
although they regard some inland alluvial
diamond deposits, particularly in Angola, as
promising, Levinson et al. (1992) predict
that the most significant new diamond
sources of the 21st century will be newly
discovered kimberlite pipes in Siberia and
northern Canada. Economically viable kimberlites, they point out, are amenable to
large-scale mining and discouraging to
illicit "pirates": two-thirds of world
diamond production in 1990 came from just
eight large kimberlite mines. The Russian
and Canadian cratons are vast, and huge
swarms of diatremes may well lurk under the
glacial cover in under-explored or
unexplored regions (the very rich diatreme
now being exploited by the Ekati mine
remained successfully camouflaged for a long
time under the glacial meltwater of Lac de
Gras).
Levinson et al. also point to the geological
favorability of Antarctica, where a large
craton lurks under the ice cover. Perhaps by
the end of this century some technology will
have evolved for getting at diatremes there.
And Janse (1996) suggests that Africa may
not only continue to be a major diamond
producer, but may again become the major
producing diamond province of the world,
perhaps thanks to technological
breakthroughs at the marine deposits, or
perhaps also to new kimberlite discoveries
in central and western Africa, where
alluvial mining so far has been the only
important kind.
As a mineral collector, one might wistfully
regret that almost all of the people who
customarily seek or mine or study or write
about diamonds are interested in them solely
for their industrial or gemstone uses, or as
objects of scientific research. It would be
interesting (though probably depressing) to
know exactly how many euhedral, uncut
crystals of diamond are preserved today,
from throughout the course of the long
history of human obsession which has been
sketched here. The fine crystals in the
private collection illustrated here provide
a wonderful glimpse of a unique species in
its original state.
ACKNOWLEDGMENTS
My thanks to the owner of the specimens
featured here for making them available for
study and photography, and to Bill Birch for
reviewing the manuscript and making helpful
suggestions. My thanks also to Wendell
Wilson for executing the photography, for
preparing the other illustrations, for
providing information on early collectors,
and for locating references in the
Mineralogical Record Library. It should be
noted that the Record Library was an
invaluable resource in the preparation of
this article.
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5755 East River Road, #1317 -
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Illicit
or Blood diamonds: Africa's curse
Just as the
history of Arab States is intimately tied to
the discovery of oil in the region, the
discovery of diamonds in Africa has not only
impacted the continent's history, but has
been one of the leading causes of conflict. The link between 'blood diamonds' and conflict in
Africa and the role of international
players in the illicit diamond trade were
recently discussed at a seminar in Nairobi,
Kenya, on resource-based conflicts organized
by the Society for International
Development's East Africa Chapter. It is
interesting to note that Africa's most
conflict-ridden countries--Angola, Sierra
Leone and the Democratic Republic of the
Congo--are also the most diamond-rich
countries on the continent, as well as the
most poor and under developed. Conflict or
"blood" diamonds have fuelled wars and led
to the massive displacement of civilian
populations in many African nations. While
conflict diamonds represent a small
proportion of the overall diamond trade,
illicit diamonds constitute as much as 20
per cent of the annual world production. The
level of illegality gives an opportunity and
a space for conflict diamonds.
The link between 'Blood Diamonds', poverty and
conflict is evident in countries such as
Sierra Leone, where the rich alluvial
diamond fields of the Kono District and
Tongo Field were among the most prized
targets of the Revolutionary United Front (RUF).
In 2000, Partnership Africa. Canada (PAC)
published a report entitled "The Heart of
the Matter: Sierra Leone, Diamonds and Human
Security", which placed much of the blame
for the civil war in the country on
diamonds, describing them as "small bits of
carbon that have no intrinsic value in
themselves, and no value whatsoever to the
average Sierra Leonean beyond their
attraction to foreigners".
The report on 'Blood Diamonds' recounts the corrupting of Sierra
Leone's diamond industry, from peak exports
of 2 million carats a year in the 1960s to
less than 50,000 carats by 1998. The
country's despotic President during much of
this time, Siaka Stevens, had tacitly
encouraged illicit mining by becoming
involved in criminal or near-criminal
activities himself. When the RUF began
waging a war in 1991, Liberian leader
Charles Taylor acted as mentor, trainer,
banker and weapons supplier for the
movement. The RUF also took on the role of
diamond supplier to the illicit
international trade. "It is ironic", says
the report, "that enormous profits have been
made from diamonds throughout the conflict,
but the only effect on the citizens of the
country where they were mined has been
terror, murder, dismemberment and poverty". The PAC report supports the idea that there
was virtually no oversight of the
international movement of diamonds. In the
1990s, for instance, billions of dollars
worth of diamonds was imported into Belgium
from Liberia, even though the latter
produces very few diamonds. This can only be
explained by the fact that big and small
companies were colluding in the laundering
of diamonds in West Africa, using Liberia as
the conduit country. Much of the laundering
was done by local Lebanese traders who have
been living in West Africa for over a
century.
Lebanese immigrants began arriving in
West Africa as refugees fleeing the hardship
caused by the silk-worm crisis which struck
Lebanon in the mid-nineteenth century.
Among the earliest recipients of those
immigrants were Senegal and Sierra Leone,
then under European colonial rule. According
to Lansana Gberie, a researcher who has
written about the Lebanese connection in
Sierra Leone's diamond trade, since the
1950s, "diamonds have been the linchpin of
Lebanese business and a range of
subterranean political activities".
In her paper, "War and Peace in Sierra
Leone: Diamonds, Corruption and the Lebanese
Connection", published by the Diamonds and
Human Security Project in 2002, Gberie
describes the beginnings of the Lebanese
trade in diamonds: "Diamonds were discovered
in Kono District, in eastern Sierra Leone in
1930, and that same year, as word of the
discovery spread, the first Lebanese trader
arrived in Kono and set up shop, ahead of
colonial officials who did not want to
establish a district office there until two
years later. They were also ahead of the
British-owned Sierra Leone Selection Trust,
which was granted exclusive diamond mining
and prospecting rights for the entire
country in 1935. From that time until 1956,
when an alluvial diamond mining scheme was
enacted, it was illegal for anyone not
working for the Trust to deal in any way
with diamonds. However, illicit mining
activities were rampant, with many Lebanese
subsequently settling in Kono and funding
Africans to mine and sell their finds to
them."
In the 1950s, the illicit diamond mining
and smuggling increased dramatically,
and it was estimated that 20 per cent of all
diamonds reaching the world's diamond
markets were smuggled from Sierra Leone,
largely through Liberia and mainly by
Lebanese and Mandingo traders. In later
years, civil war often revolved around the
control of this illicit trade. In 2002, a UN
Expert Panel reported that the then
"interim" leader of the RUF, Issa Sesay, had
flown to Abidjan late in 2001 with 8,000
carats of diamonds that he had sold to two
traders of undisclosed identity, who were
apparently using a Lebanese businessman to
run errands for them between Abidjan and the
Liberian capital, Monrovia. Some reports
suggest that the UN peacekeeping force in
Sierra Leone may have also become involved
in the RUF illicit diamond trading.
In 2001, shortly after the 11 September
attacks in New York and Washington,
D.C., the Washington Post found another link
in this most secretive and highly lucrative
trade--that of international terrorists. In
an article published on 2 November 2001, war
correspondent Douglas Farah stated that the
Al Qaeda network "reaped millions of dollars
in the past three years from the illicit
sale of diamonds mined by rebels in Sierra
Leone" and that three senior Al Qaeda
operatives had visited Sierra Leone at
different times in 1998 and later. He
further claimed that the West African
Shi'ite Lebanese community was sympathetic
to Hezbollah and often served as a link
between the RUF rebels and Al Qaeda.
However, according to Gberie, much of the
evidence linking West Africa's Lebanese
community to global terror networks is
largely "anecdotal and circumstantial".
In the last few years, however, the
illicit diamond trade has come under
scrutiny from many quarters, which makes
it much more difficult for middlemen and
smugglers to operate. Since 1999, PAC has
undertaken a program of policy research,
education and advocacy to ensure that the
international diamond industry operates
legally, openly and for the primary benefit
of the countries where the diamonds
originate. It has also extensively published
reports that have uncovered the secret
dealings and James Bond-style maneuvers of
the middlemen and smugglers in the industry
who operate often with the full knowledge
and approval of Governments (or rebel
movements), and act as conduits for diamonds
smuggled from neighboring countries.
In May 2000, an international certification
process for rough diamonds, known as the
Kimberley Process, was initiated by
the Government of South Africa.
Concerned about how diamond-fuelled
wars in Angola, Sierra Leone and the Democratic Republic of the Congo might
affect the legitimate trade in other
diamond-producing countries, more than 35
nations have been meeting on a regular basis
to develop the system, which was established
in 2003.
In Sierra Leone, the diamond certification
system was instituted in October 2000, four
months after the UN Security Council passed
a resolution that banned diamond exports
until a certification system was set up. In
the twelve months after the system was
introduced, legal exports rose from $1.3
million to $25.9 million worth of diamonds.
However, PAC believes that many of the
better quality diamonds are still being
smuggled and are not going through the
official certification system. In other
words, the illicit diamond trade continues
to operate through informal agreements that
are sealed with a nod, a wink and no paper
trail.
Author
Rasna Warah, a freelance writer based in
Nairobi, is a Board member of the East
Africa Chapter of the Society for
International Development.
COPYRIGHT United Nations Publications,
COPYRIGHT Gale Group
- Diamonds are
forever - and greed -
Many see expensive diamonds as the perfect gift for
their significant others. Yet, couldn't some
other gem have the same impact? There is an
extraordinary logic to the diamond trade:
Diamonds are presumed of value because they
are pricey. Consumers are told they are
pricey because they are rare and expensive
to cut. Are they really? After all, flawless
diamonds can be produced in a laboratory. A
"mined" diamond and a "lab" version are
tough to tell apart. Little wonder, since
both are crystallized carbon. Of course,
concern over the price of gems pales in
comparison to the horrible sight of children
whose arms have been amputated by the thugs
who tam diamond mines in West Africa, or the
knowledge that Al Qaeda trades in diamonds
purchased from these same mines.
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Responding to the outcry of its citizens,
Congress passed the Clean Diamond Trade Act
in 2003 to guarantee that gems purchased
in the U.S. be free from all human rights
abuse. Is this legislation working? Are the
diamonds in our stores guaranteed to be
clean? I set out to answer these and other
questions using the Freedom of Information
Act. I searched the records of the Justice
and State Departments for information on
this lucrative trade and on De Beers, the
company that controls 65% of the world's
diamond supply. In 1942, the Justice
Department began an investigation of De
Beers that is still ongoing. I went through
thousands of pages of intercepted cables,
spy reports, Nazi documents, and eye-opening
mail. These brutal diamond wars have been
going on fur decades. Moreover, terrorists
have long used the precious diamond stones to fund
their egregious activities.
Documents reveal highly secretive
diamond price-fixing operations that run rings
around the Justice Department, Congress, and
the White House. The strategy is quite
simple, actually: American diamond merchants
pick up their supply from De Beers in London
where U.S. laws banning exploitative price
fixing do not apply. De Beers moves diamonds
along clandestine routes used by drug barons
and arms merchants. I traced these trails, I
found De Beers has its own area in
Switzerland's Zurich Airport where, as a
customs official explained to me, it can fly
in a diamond from Africa, and, within a day,
legally arrange for it to be given papers
identifying it as Canadian. The United
Nations claims that this tactic |

Diamond Stones
Cullinan Mine |
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makes it near impossible to trace
terrorist-linked diamonds. De Beers,
incidentally, is controlled by a family
company registered in Liberia.
International trading statistics show
that diamonds sent from Switzerland to the
United Kingdom surprisingly multiply by
three times en route. In 1982, for example,
UK customs recorded 10 times more stones
arriving from Switzerland than Switzerland
said it had sent. Some years, by similar
means, thousands of gems vanish into thin
air. As for the diamond-producing countries
of South Africa, Namibia, and Botswana,
their gems may seem to disappear from
international circulation overnight.
After reviewing documents and traveling
around the world to investigate the many
leads they supplied, I wrote a proposal fix
a television special called "The Diamond
Empire." It appeared in 1994 as a
feature-length "Frontline Special" on PBS
and as a three-part BBC series. Filming was
not an easy project to complete. Everywhere
I went. De Beers had phoned merchants
telling them not to speak with me.
Gradually, though, I untangled The diamond
cartel's web, shooting footage in India,
Europe, and the U.S. Then a gang broke into
my home and assaulted me, shattering several
of my facial I bled heavily from the wounds
head. The next day, there was a surprise
attempt to take over the documentary I
withstood this, but medical complications
soon set in. I spent two months in the
hospital. For two of those weeks, I was in
critical condition. I could not edit the
film myself. PBS cut it to my script, but
the BBC censored its version under heavy
pressure from De Beers. When I came out of
the hospital, I was determined to complete
my investigation and publish the findings
uncensored. |
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Diamonds once were genuinely rare--about
140 years ago--after the diamond mines
practically ran dry in India. Then
diamonds were discovered by the thousands
literally sparkling in the moonlight in
southern Africa. Merchants who had invested
huge sums of money in the few remaining
diamond mines in India panicked. They feared
their investments would plummet in value.
So, they funded South African politician
Cecil Rhodes to set up De Beers. He had all
the cash needed to buy up the diamond
deposits of South Africa. In return, he
agreed to sell the entire output to the
"Diamond Syndicate" comprised of these same
merchants. Thus, they kept the price high.
In the 1930s, the Oppenheimer family gained
control over De Beers and the Diamond
Syndicate.
I first became interested in diamonds in
1979. I was working on civil rights issues
with Aborigines in the far northwest of
Australia when a major diamond deposit was
found nearby in a sacred valley called
Barramundi Dreaming, where for centuries
women had gone to pray and meditate. Some of
these women took me to see the site before
it was destroyed by the diamond rush. There
was a beautiful, sparkling stream surrounded
by fat-trunked boab trees. When I looked
into the water, there were hundreds of
diamonds, lying like glossy pebbles in its
bed. Later, I learned from local geologists
that there were up to 27 carats of diamonds
in every ton of rock underlying the stream's
headwaters. Today, this locale is an
enormous pit, full of excavators and tracks.
It is producing up to |
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eight tons of diamonds a year at a
cost of less than $10 a carat.
Supposedly, De Beers was reaping a
mere one-fifth of a carat diamond stone for every ton of
mined rock in Africa. However, Canada has
diamond deposits with four carats per ton,
and some Russian mines produce 10 carats a
ton. Why then were the South African mines
doing so poorly? I met a diamond prospector
who had worked as an overseer in De Beers'
mines. He told me that sometimes they broke
into pockets where gems were so plentiful
that they would tumble out onto the ground.
When this happened, the overseers literally
would shovel up the diamonds into buckets.
Was I being spun a story? I went to South
Africa to investigate and met with
miners and geologists working for De Beers.
They confirmed the details. In fact, I heard
tales of more than 3,000 carats of diamonds
tumbling out of the rocks within the De
Beers mines. In Kleinzee, I visited a vast
mine on the wild Atlantic coastline,
where diamonds lie under giant sand
dunes roamed by ostriches and edged
by fierce surf. The wife of the
mine's chief geologist took me on a
tour. She commented on the fine gems
under the dunes and on the nearby sea floor,
washed from dormant volcanoes that hi
ancient times spilled diamonds onto the
Earth's surface. Offshore, De Beers' vessels
were sucking up diamond stones from the
seabed. |

Diamond Stone
Cullinan Mine |
On its
first trip, one vessel grabbed up nearly
5,000 large diamond stones in a week. These are
canned like peas to keep them secure. The
head of the South African Diamond Board
imparted, "We do not shout it from the
rooftops, but diamonds are not rare, except
for some qualities."
I watched the mineworkers dig. Giant
excavators removed the sand. Some laborers
used vacuum hoses connected to large yellow
safes on wheels to swallow up exposed
diamonds. Others formed lines, bending over
to examine every tiny crevice in the rocks.
In one hand they held a brush, in the other
a metal prong, thus earning the nickname
"bedrock cleaners." They are paid so little
that De Beers calculates that it costs a
mere 40 cents a yard to clean a beach. The
company recently agreed to pay a minimum of
$50 a week, but not for long. It is
replacing the union mineworkers with
subcontracted laborers to be paid only
$20-30 a week. De Beers officially
calculates that each one of its 3,000 miners
at Kleinzee produces, on average, over
$1,600 worth of diamonds every seven days.
Many maintain that this estimate is quite
conservative. I asked a group of black diamond mineworkers
if they bought their loved ones engagement
rings. They laughed. "De Beers brings us
divorce, not love!" they claimed. They
explained that since they were in the lowest
wage bands, they were not entitled to
married housing. Instead, they lived in
single men's barracks. If their wives got a
job in the mining town, say as a cleaner or
cook, they had to stay in the single women's
quarters. They were punished if found to be
sleeping with their partners. This comes as
no surprise. Remember, De Beers helped
create apartheid in order to gain control
over its workforce.
The mine has very tight security. If
an ostrich accidentally is killed on the
grounds, its corpse has to go to company
security to make sure it has not swallowed a
diamond. The man who operates the X-ray
machine revealed that he had to give workers
a whole-body scan every day in order to
ensure that nothing was smuggled out. He
confessed he concealed the health danger by
not recording all the X-rays in the mine's
records. I subsequently investigated a
larger coastal mine--covering hundreds of
square miles--in Namibia, known historically
as "The Forbidden Zone." I found working
conditions there much the same.
I visited De Beers' inland mines as well,
including one where diamonds literally were
picked out of asbestos rock. The dust was so
thick that miners sometimes could not see
their fingertips. For protection, all they
bad was a simple nosebag--a piece of cloth
that was black with dust within 20 minutes.
Medical statistics were unobtainable; they
were kept confidential by De Beers. The
company also is able to conceal diamond
deposits by having them secluded inside game
reserves, where mining is forbidden. The
company allegedly trucks in antelope for the
sake of appearances. Another major deposit
was concealed within the Kalahari Desert in
Botswana, on lands traditionally owned by
people with the most ancient culture
surviving in our world, that of the Bushmen.
In 2002, the Botswanaan government evicted
the entire population, maintaining it was
for assimilation purposes.
The Bushmen say they have been moved to
"death camps." De Beers, however, has no
intention of mining these diamonds any day
soon. They have placed a concrete slab over
the mining shaft. De Beers Chairman Nicky
Oppenheimer
even boasts that the concrete is so thick
that "I can land my helicopter on top of
it."
Nine in 10 of the world's diamonds are
cut in India by individuals who were paid 40
cents per gem. Those wages were slashed
to 20 cents in 2001. Today, the average pay
to cut and polish a diamond for the American
market is 23 cents. Eight-year-olds are
cutting diamonds. This industry is hazardous
because of fast-moving belts and airborne
diamond dust. I estimate that consumers are
paying at least 10 times too much for the
diamonds they purchase--but that is nothing
compared to the cost to exploited diamond
workers (many of them children) around the
world.
Author
Janine Roberts is the author of Glitter and
Greed: The Scorer World of the Diamond
Cartel.
COPYRIGHT Society for the Advancement of
Education, COPYRIGHT Gale Group |
- Diamond
Cutting Basics
The art of diamond cutting is not
particularly old in the western world.
It is believed that Europeans traveling
to India first picked up the basic idea
from the Indians but it was not until
the sixteenth century that anything of
value came out of the early experiments.
Some of these early cuts were called
rose cuts because they resembled the
look of roses. Basically, they were
triangular shaped facets cut in a
symmetric pattern on the top of the
diamond with the bottom of the diamond
left flat for mounting into something.
However, it was not until the 20th
century that a full application of the
technology of reflecting light was
applied to diamond cutting. Today
mathematical calculations on computers
are often used to help determine the cut
of a diamond. There is still an art to
cutting diamonds but science is the
bigger factor in modern cut diamonds.
Diamonds when they are first mined
are relatively bland looking. You
could easily mistake one for just a
simple shiny rock or over look it
completely. It is estimated that 98
percent of the brilliance of modern cut
diamonds comes from the cut, not the
clarity, size or color, so the cut of a
diamond is extremely important. The cut
or make of diamonds is actually the sum
of 3 separate factors:
1. The proportions of the cuts, 2.
The finish or polish of the diamond and
3. The symmetry of the diamonds facets.
The complete purpose of all three is to
reflect as much light back out of the
diamond as is possible, to figuratively
light up a dark room.
Of these three the proportions
represent the actual finished overall
shape of the diamond. Although the
exact dimensional ratios for an ideal
cut diamond have not been agreed upon
internationally, the terminology used is
standard around the world. Table, crown,
crown height, crown angle, girdle,
pavilion, pavilion depth and pavilion
angle are the basic standard terms used
to describe the proportions of a cut
diamond. If you look down at a diamond
set in a diamond ring the top most flat
part is called the table. The largest
diameter of the diamond as you look down
on it further is called the girdle. This
top part of the diamond from the girdle
up to the table is called the crown and
of course the crown height and crown
angle refer to the depth of this part of
the diamond and the angle from the
girdle up to the table. The part of the
diamond that you don't see when you look
down at a diamond ring is called the
pavilion, the part from the girdle down
to the bottom of the diamond. The bottom
of a modern diamond is generally
pointed. The distance down from the
girdle to this point is called the
pavilion depth. The angle from the
girdle edge to this point is the
pavilion angle.
The polish of a diamond is pretty
much self-explanatory. It is a lot
like when you polish your car. Sometimes
there are marks left and sometimes the
car wash does a better job than other
times.
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In a similar fashion, the diamond finish is
graded by the diamond industry.
Good, very good, excellent and ideal for
example are grade designations for polished
diamonds.
The symmetry of a diamond refers to
the shape, size and proportions of the
facets cut into the crown. Are the
facets all of consistent shape around
the crown of the diamond? Do the points
of one facet align perfectly with the
next facet? Are the lines of the cuts
straight or wavy? Are the facets
perfectly flat? These are questions used
to define the symmetry of a modern cut
diamond.
Author
Michael Russell
Your
Independent guide to Diamonds, http://diamonds.your-buyers-guide.com |
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