A diamond is forever. So are sapphire, silica and Styrofoam. It is the hardest known naturally occurring substance, which explains why diamonds are excellent industrial cutting materials, not emblems of romance. They are no more rare than any number of minerals, no more dazzling. So although diamonds may have their genesis in the heat and pressure of the earth’s mantle billions of years ago, what a diamond represents is a very modern tale.
In 1870 British mining efforts in South Africa uncovered massive diamond deposits. Until then, as commodities, diamonds had been extremely rare; the new finds threatened to flood the market with stones and obliterate their price. Investors in the mines realized they had to consolidate their interests to control the flow of diamonds into the open market, and so in 1888 they formed the De Beers Consolidated Mines Ltd. consortium. By stockpiling its goods to keep prices high, De Beers controlled the worldwide diamond supply for the next century.