Diamond's belong to the most wanted items worldwide and it has been like this for centuries. Everybody knows what a diamond looks like and nobody would mind if their were being presented with a diamond, but what exactly is a diamond? We all know its very hard (in fact, its one of the hardest materials at all), we all know its shiny and we all know that diamonds are a girls best friend. But how come they are what they are?
Against a popular misconception, diamonds are not found in the way we get to see them. The diamond in your ring, all shiny and perfectly shaped, was cut from a rough diamond crystal. This rough diamond is hard, not quite as shiny as the one in your ring and it still has to go a long way to look the way we want them to look. The main thing that has to happen is that the diamond has been analyzed to find out what cut and shape would be perfect and then it has to be cut. This process appears to be easy in the first place, but it actually is very complicated. To give you a picture of this process, I'll tell you about the world's largest diamond ever found, the Cullinan Diamond.
The Cullinan Diamond is the world largest rough diamond ever found, weighing 3,106.75 carats or 621.35 gram. It was found in the Premier Mine in what today is South Africa. Now without knowing anything about diamonds, one might say the polished diamond would weigh slightly less then the rough diamond. But in fact, the largest polished diamond cut out of the Cullinan is the Cullinan 1, weighing "only" 530.2 carats or 106 gram. Occasionally, the Cullinan Diamond was cut into 9 larger stones and a number of smaller fragments.
This was done because the appearance of a diamond the way we prefer it – shiny and brilliant – is dependent on several factors. The 2 primary ones are the refractive index (RI) of a diamond and the diamond's dispersive power. A diamond's RI is the factor responsible for its brilliance, or the amount of incident light reflected back to the viewer. The diamond's dispersive power is its ability to split white light into its components – the spectral colors. These flashes of spectral colors are called "fire". Both brilliance and fire only become impressive after cutting. That's why the cutting is so important and so complicated at the same time. Choosing a wrong cut means reducing the value of the cut and polished diamond. Choosing the right cut and cutting it professionally means upgrading the value.