Diamonds were formed deep under the earth’s crust more than three billion years ago. Intense heat and pressure – 1,000 C and 50 kilobars – caused carbon to crystallize into diamonds.
Their use waned after the rise of Christianity, and fall of Roman Empire, as they were seen as pagan. However, once Christianity was entrenched, the lure of the diamond reasserted itself.
Volcanic activity forced the diamond-bearing rock 300 kilometers upwards, towards the surface of the earth. After it cooled, it solidified into blue ground, or kimberlite, where the precious rough is found.
Erosion by rain, flood and wind released many of the diamonds and carried them down riverbeds, where they form alluvial deposits, or out to sea. In their journey from under the earth’s crust – and into rivers and the sea – many diamonds are crushed.
It takes many hundreds of tons of rock to produce one carat of diamond, so remember that diamonds are very rare.
The word diamond comes from the Greek word ‘adamas’ meaning hard. The ancient Greeks and Romans believed diamonds were the tears of the Gods and splinters from the stars. Diamond engraving tools were used in Rome soon after 14 BC, and diamonds then made their appearance in Roman jewelry.
Their use waned after the rise of Christianity, and fall of Roman Empire, as they were seen as pagan. However, once Christianity was entrenched, the lure of the diamond reasserted itself.
The earliest evidence of diamond cutting was in 1330 in Venice – long the trading capital for goods moving from the East to the West. The cutting technique followed the trade route to Bruge and then to Paris.
True gems – fashioned diamond jewels – appeared in Europe after 1380. That means that by then, there must have been a steady increase in trade, some availability of colorless stones and the development of cutting skills.
The earliest documentation of diamond trading was in Antwerp in 1447. European exploration for trade routes, such as by the Dutch East India Company, increased the availability of diamonds in the West.
The discovery of the South African diamond fields in the nineteenth century changed history. Suddenly far more diamonds were available. For the first time, supply of diamonds could meet demand.
Combined with increased wealth in Europe and the USA, diamond ownership became democratized. Diamonds were no longer just for royalty or the extremely wealthy, but were adornments for everyone.
Cecil John Rhodes arrived in South Africa from England in 1870 at the age of 17. He purchased a mining claim in the De Beers mine (named after the farm where the deposit was discovered).
When he graduated from Oxford in 1881, he returned to South Africa and formed the De Beers Mining Company with some associates. They actively bought more and more mining claims – and by 1887, he had gained complete control of the De Beers Mine. With some clever financial maneuvers, he managed to wrestle control of the Kimberley Mine from his rival Barney Barnato. Barnato sold Kimberley Central to Rhodes for £5 million pounds – at that time the biggest check ever issued.
Rhodes merged Kimberley Central into a new company, De Beers Consolidated Mines, which he controlled. At the beginning of the twentieth century Rhodes’ company controlled almost all of the world’s diamond production.
In the 1940s, an advertising team from NW Ayer came up with the memorable slogan ‘A Diamond is Forever’. This immortalized the diamond as the ultimate gift of love.
It has been voted the best advertising tagline in the history of advertising. Everybody loves it, because it’s true. Diamonds are forever.
Carat is often confused with size even though it is actually a measure of weight. The cut of a diamond can make it appear much larger or smaller than its actual weight.