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Diamond Sources

[edit]
Diamond output in 2005

The diamond supply chain is controlled by a limited number of powerful businesses, and is also highly concentrated in a small number of locations around the world (see figure).

Only a very small fraction of the diamond ore consists of actual diamonds. The ore is crushed, during which care has to be taken in order to prevent larger diamonds from being destroyed in this process and subsequently the particles are sorted by density. Today, diamonds are located in the diamond-rich density fraction with the help of X-ray fluorescence, after which the final sorting steps are done by hand. Before the use of X-rays became commonplace, the separation was done with grease belts; diamonds have a stronger tendency to stick to grease than the other minerals in the ore.[1]

Historically diamonds were known to be found only in alluvial deposits in southern India.[2] India led the world in diamond production from the time of their discovery in approximately the 9th century BCE[3] to the mid-18th century AD, but the commercial potential of these sources had been exhausted by the late 18th century and at that time India was eclipsed by Brazil where the first non-Indian diamonds were found in 1725.[4]

Diamond production of primary deposits (kimberlites and lamproites) only started in the 1870s after the discovery of the Diamond fields in South Africa. Production has increased over time and now an accumulated total of 4.5 billion carats have been mined since that date.[5] Interestingly 20% of that amount has been mined in the last 5 years alone and during the last ten years 9 new mines have started production while 4 more are waiting to be opened soon. Most of these mines are located in Canada, Zimbabwe, Angola, and one in Russia.[5]

In the United States, diamonds have been found in Arkansas, Colorado and Montana.[6][7] In 2004, a startling discovery of a microscopic diamond in the United States[8] led to the January 2008 bulk-sampling of kimberlite pipes in a remote part of Montana.[9]

Today, most commercially viable diamond deposits are in Russia, Botswana, Australia and the Democratic Republic of Congo.[10] In 2005, Russia produced almost one-fifth of the global diamond output, reports the British Geological Survey. Australia has the richest diamantiferous pipe with production reaching peak levels of 42 metric tons (41 long tons; 46 short tons) per year in the 1990s.[6] There are also commercial deposits being actively mined in the Northwest Territories of Canada, Siberia (mostly in Yakutia territory; for example, Mir pipe and Udachnaya pipe), Brazil, and in Northern and Western Australia.

  1. ^ Harlow, G. E. (1998). The nature of diamonds. Cambridge University Press. p. 223. ISBN 0521629357.
  2. ^ Catelle, W.R. (1911). The Diamond. John Lane Company. Page 159 discussion on Alluvial diamonds in India and elsewhere as well as earliest finds
  3. ^ Ball, V. (1881). Diamonds, Gold and Coal of India. London, Truebner & Co. Ball was a Geologist in British service. Chapter I, Page 1
  4. ^ Hershey, J. W. (1940). The Book Of Diamonds: Their Curious Lore, Properties, Tests And Synthetic Manufacture. Kessinger Pub Co. p. 28. ISBN 1417977159.
  5. ^ a b Janse, A. J. A. (2007). "Global Rough Diamond Production Since 1870". Gems and Gemology. XLIII (Summer 2007). GIA: 98–119. doi:10.5741/GEMS.43.2.98.
  6. ^ a b Lorenz, V. (2007). "Argyle in Western Australia: The world's richest diamantiferous pipe; its past and future". Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft. 56 (1/2). DGemG: 35–40.
  7. ^ "Microscopic diamond found in Montana". The Montana Standard. 2004-10-17. Retrieved 2008-10-10.
  8. ^ Cooke, Sarah (2004-10-19). "Microscopic Diamond Found in Montana". Livescience.com. Retrieved 2008-09-12.
  9. ^ "Delta News / Press Releases / Publications". Deltamine.com. Archived from the original on 2008-05-26. Retrieved 2008-09-12.
  10. ^ Marshall, Stephen (2004-10-22). "The Diamond Life". Guerrilla News Network. Archived from the original on 2008-06-09. Retrieved 2008-10-10. {{cite web}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)