The birth of a diamond is a long and hard process. It begins 100 miles underground where extreme heat and pressure crystallize carbon into rough diamonds over millions of years. There are only a handful of places in the world where commercial diamond mining is possible. At those sites heavy machinery and explosives are used to reach the diamondrich soil deep underground in the pit mine.
The excavated ore is crushed in special machinery to be able to seperate the soil from the diamonds. Diamonds stick to grease, so this method is used to pick them up from the soil. Afterwards, rough diamonds are sorted and measured before being cut. The manner in which diamonds are cut is also dependant on their colour. The final value of a polished diamond is determined by the 4 c’s - carat, cut, colour and clarity.
Carat is a measure of the weight of a diamond, and is the same weight in every part of the world. Originally based on carob seeds used by early gem traders, nowadays the carat tells you how heavy the stone is and therefor gives you an indication of the price. If all other criteria are the same, a gem with a higher carat amount will be more expensive. Some weights are ‘magic sizes’, like the half, threequarter and one carat sizes.
The difference between a 0.9 carat and a 1.0 carat diamond may not be visible, but will affect the price drammatically.
Most diamonds found in nature are between one to three billion years old.
Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This can result in a variety of internal properties called 'inclusions' and external characteristics called 'blemishes.' Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher its value.
Diamonds are renowned for their ability to transmit light and sparkle so intensely. We often think of a diamond's cut as shape (round, emerald, pear), but a diamond's cut grade is also about how well a diamond's facets interact with light. The combination will of the shape and the ligh interaction determines the sparkle of a diamond.
Color manifests itself in a diamond as a pale yellow. This is why a diamond's color grade is based on its lack of color. The less color a diamond has, the higher its color grade. After cut, color is generally considered the second most important characteristic when selecting a diamond. This is because the human eye tends to detect a diamond's sparkle (light performance) first, and color second.