Does equipment technology now threaten the diamond mining industry? Two news items raise this fear:

  • Dwyka Diamonds announced that commercial recovery of diamonds from the old Kimberley De Beers tailings pile is successfully being accomplished by means of its state-of-the-art dense media separation plant that uses X-ray sorting followed by a purpose-built, high-capacity grease belt. Planned throughput is eighty to one-hundred thousand tons per month.
  • De Beers produces synthetic diamonds at Springs (where I grew up) east of Johannesburg (where I went to University) and at Shannon in Ireland (where I have never been). Now Gemisis will produce cultured gem diamonds in Sarasota, Florida. Gemisis’s process is not new—it was first developed a quarter of a century ago in the old Soviet Union and then bought and developed over the past dozen years in the States. Competing with them is Apollo, using a vapor deposition technology at its facility in Boston, Massachusetts. (Read more on )

Nomenclature in the Future. The "natural" diamond producers have reacted initially to the advent of "cultured" by legal action in Germany to block Gemisis using the German word for cultured. They would prefer the word "synthetic" with all its connotations. German judge ruled against Gemisis, but what of the English language—can U.S. courts set terminological standards?

Future Marketing Speculations. Gemisis’s "cultured" stones are all-American—they are demonstrably not tainted blood diamonds or diamonds from countries where politicians and civil servants may have been unduly influenced financially. Remember what happened when American women were persuaded that natural furs were associated with the murder of species and tainted by animal blood. Fur sales collapsed in the States. American cultured diamonds are demonstrably produced by ethical means. Cultured diamonds are cheaper to produce than those hauled by De Beers out of the bottom of Jwaneng—a quarter to half the price per carat. The retail selling price of a cultured diamond is in the region of $12,000 a carat, around half that of the "natural" equivalent.

Nomenclature Background (for the geologist): Dwyka Diamonds probably takes its name from the Dwyka Tillite. Here is a brief description of the geology of that that deposit. The tillites were deposited in a glacial environment by retreating ice sheets 300 million years ago. At that time South Africa was part of the supercontinent Gondwana, which was situated near the south pole and covered with ice. Rocks imbedded in the slowly moving ice sheets scoured and polished the underlying older rocks giving rise to glacial pavements. Striation directions indicate that ice flow was from north to south - valuable information when it comes to reconstructing Gondwana. The Dwyka Group forms the lowermost and oldest deposit in the Karoo Supergroup basin. This basin extended across much of southern Gondwana and records 120 million years of geological history. Clearly natural diamonds predate the glaciation. Maybe this is the connection--from the Pioneer Diamond Project: Diamondiferous gravels occur as extensive alluvial gravel terrace deposits flanking the Orange River Valley. Gravels are found on a planar surface with bedrock comprising Ventersdorp lava (Precambrian) and Dwyka tillite and shale (Carboniferous). The gravels deposits were deposited between Late Tertiary and Quaternary times. Gravel deposits are of considerable thickness often in excess of 7 meters.

Unconformity of Dwyka tillite (300 Ma old) on top of Late Archean metavolcanic rocks of Vertersdorp Supergroup.


Meanwhile there is no obvious concern in Canada: This from © 2006 The Canadian Press:

Anglo-Australian mining giant BHP Billiton (NYSE:BHP) has approved a major expansion of its Ekati diamond mine in the Far North just a few days after the company reached agreement on a first contract covering 375 workers at Canada's first diamond project. BHP Billiton announced that the Koala underground project at the Ekati mine, projected to cost $250 million US, had received approval. Initial production from the development in the Northwest Territories is expected to begin in the fourth quarter of 2007 and full production is expected to be reached by mid calendar year 2009, BHP Billiton said.

The project is slated to recover about 9.8 million carats of high value Koala diamonds over an 11-year production life.

BHP Billiton's share of the expansion is about $200 million US. "The development of the Koala underground project follows the successful completion of the Panda underground mine at Ekati, earlier this year," Alberto Calderon, BHP's president of Diamonds and specialty products, said in a statement. "Koala underground will supply around 25 per cent of the mine feed (3,300 tonnes per day) to the plant while producing 40 per cent of the diamond output by value. As well as delivering margins three times greater than the material it displaces, this development will also partially offset the natural decline in production grades and quality that occurs as the mine matures."

The mine, located about 300 kilometres northeast of Yellowknife and 200 kilometres south of the Arctic Circle, is BHP Billiton's only diamond operation and accounts for about four per cent of the world's diamond output by weight and six per cent by value.