If this does not say "I love you," you haven't
been watching enough De Beers ads!
Courtesy Jill
Banfield.
See the movie (72K):
Diamonds are carried to the surface by volcanic eruptions in a kimberlite
pipe.
Courtesy Jill
Banfield.
The Ekati mine, now operating in the Barren Lands, is expected to yield $500-million in diamonds (about 1,000 kilograms) a year for 17 years. Several other mines will open nearby.
It's cold and it's remote, but the Northwest
Territories has oodles of diamonds.
Government
of the Northwest Territories.
Want
a Valentine's rock? Then you can't beat diamonds. Born of Earth, harder
than nails, and ooh-soo-dear, diamonds are the rock of love. Just ask De
Beers, which has manipulated the diamond market so long and so well in its
effort to position diamonds as the true symbol of love.
Like the ideal love, a diamond is, well, forever. But just as neglect can ruin love, heat or a nasty whack with a hammer can destroy a diamond.
Iceman cometh. Ditto profits
Forever is how long the De Beers hammerlock on the market has seemed
to last. In the past few years, however, some unpleasant realities have
intruded on its secretive, profitable business of mining and diamonds
and finessing the market.
Rebels in Angola and other African nations have used diamonds to fund bloodthirsty civil wars. The nasty publicity forced De Beers to eschew "conflict diamonds" -- rocks sold to buy weapons for groups that use child soldiers and commit atrocities.
Like the graphite used in pencil lead and some lubricants, diamonds are
a crystalline form of carbon. But graphite's cheap and soft; diamonds
are expensive and the hardest natural element (they are also an excellent
conductor of heat).
Diamonds, like many crystals, are also quite durable, and "Diamonds are forever" turns out to be more than just an annoying pitchman's slogan.
Diamonds are ancient crystals, formed deep underground when carbon is subjected to high temperature and enormous pressure (just how hot, and how crushing, and for how long we wish we knew. In the diamond biz, those who know don't tell, and those who tell tend not to know...).
Current theories say diamonds form 100 or more kilometers below ground, in ancient rocks called cratons that have been little disturbed by the incessant jostling of continental plates. The crystals can form in cratons because they have the necessary pressure, but are cooler than other places with similar pressure.
Up the tubes
Diamonds usually reach Earth's surface in kimberlite
pipes, igneous structures that rise due to their high temperature and
Earth's huge internal pressure. The so-called "pipes" are roughly circular,
and up to a few kilometers in diameter.
Kimberlite pipes used to be considered rare, says William Sharp, a retired geology professor from the Colorado School of Mines, but about 300 pipes were discovered in Canada Barren Lands alone over the past decade.
A: terraces on excavation wall.
B: access ramp for vehicles.
C: Blast pattern now being drilled.
D: deepest part of pit. The bright spots above and to the left of "D" are giant scoop shovels and haul trucks.
E, F, G, H: Giant machines.
Courtesy Canadian Centre for Remote Sensing.
The Barren Lands are a vast stretch of bedrock covered by low vegetation and endless lakes and swamps. Buggy in the summer, it's piercingly cold in winter.
The
emergence of Canada's Northwest Territories as a center of diamond production
owes to the dedicated -- some would say maniacal -- efforts of Charles
Fipke, a Canadian prospector who tracked the gems for a decade.
Fipke's search, ably chronicled in "Barren Lands" (see bibliography), was an epic of dogged determination, spiced by death-defying experiences and plenty of prospector's skullduggery.
Although many kimberlite pipes don't contain diamonds, plans are in the works to mine at least a dozen in Canada. Russia also has large diamond reserves -- but the problems of cold and inaccessibility are, if anything, even worse than in the Barrens.
Kimberlite rock itself is hard, igneous stuff, and mining requires expensive drilling and blasting, says Sharp, who spent many years working at mines in Congo, then called Zaire.
Ice moves ice
Since diamonds are so rare -- even in a good mine,
they appear in parts per million, prospectors search for the "indicator
minerals" that cohabit with diamonds. Since glaciers shaped the Barren
Lands, Fipke realized that the indicator minerals he was finding must
have emerged from a kimberlite pipe closer to the source of the ice.
In prospector's parlance, Fipke and his driven crews moved "up-ice" and eventually located the source near Coppermine, a mining town (you wouldn't guess from the name) in the middle of nowhere in the Northwest Territories.
The first major North American strike threatened the De Beers monopoly by increasing production outside the De Beers mainstay, Southern Africa. De Beers ably sidestepped the threat by making a successful hostile offer for one Canadian mine, and by arranging to market one-third of the output of another.
(For a survey of masterful, modern-day market manipulation, see "The De Beers Story..." in the bibliography).
The Hope Diamond, India. Smithsonian Institute.
The diamond trail
In
recent years, diamond prospecting has adopted the modern analytical tools
of physical science, allowing ever-more precise analysis of diamonds and
the all-important indicator minerals.
Non-destructive testing techniques show that diamonds are not created equal -- they are not identical. "We assumed diamonds were 100 percent carbon," says Sharp, "but they contain a lot of trace elements in the ppm [parts-per-million] range."
These elements lend color to diamonds, and, Sharp says, and "Color is a kind of fingerprint, you can almost take it back to its source. It would not surprise me in a few years if you could take a diamond off a lady, analyze them, and conclude that it came from Angola, Russia, or the Kimberley pit." (Kimberley, incidentally, is the rich South African mine that loaned its name to kimberlite, the rock formation.)
Such an analysis might help track the diamonds that are funding bloodthirsty rebellions, but that's veering far from our Valentine's theme.
Bowerbirds: These romantics need no diamonds.
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