The arid deserts of South Africa. The permafrost of Siberia. A barren region of Western Australia. Frozen tundra in Canada’s Northwest Territories. The featureless ocean off the southwest coast of Africa. That diamonds form at all is something of a miracle. That they survive a brutal and violent trip up from deep inside the earth is another. And that people cherish them enough to seek them out in such remote and inhospitable places is a third.
Mining companies not only have to dig mines and build large processing plants in remote locations, but they must build the equivalent of small cities to house, feed, and entertain hundreds of workers.
Mining involves a lot of money and labor for relatively small quantities of diamonds. It costs millions of dollars to identify a possible diamond deposit. It costs even more to build and operate a mine in a location that’s found to contain diamonds.
The ratio of diamond to ore is usually about 0.30 ct. of rough diamond per metric ton (1.102 US tons) of ore. That means mine workers have to process about a ton of rock to recover less than half a carat of rough diamond. Obviously, amine can’t survive if the ore doesn’t yield enough diamonds to cover the mining costs.
Unlike apples - which grow on trees - the supply of diamonds at any given mine is limited. The Ekati mine in Canada, for example, started production in 1998. Current projections are that it will operate for about 20 more years, and produce 3 to 4 million carats of rough diamonds per year.
The quantity of a mine’s diamonds isn’t the only factor in its profitability. The quality of the diamond matters, too. Some mines produce lots of low quality diamonds. Others produce fewer, better quality diamonds. Diamonds are expensive because they’re rare and costly to mine.
