Diamond

Diamonds are normally sold according to their 'grade' and they are graded using the 4 C's these are colour, clarity, cut and carat. To be sure of these grades the gemstones need to be assessed loose, before they are set in the piece of jewellery.

Colour – Generally diamonds appear to be colourless, however it is possible to purchase diamonds with very distinct colouration. Within what most people would call a colourless diamond there are a variety of grades each of which is given a letter to identify it, these range from the top grade of D – colourless through to M and further through the alphabet to diamonds that are almost brown in colour.

Clarity – The vast majority of diamonds have inclusions within them and these are natural characteristics of the gem (many forms of gemstones have inclusions). The size, colour and distribution of these features determines the clarity grade which is in the form of a letter or letters e.g. diamonds that have no visible inclusions when studied under 10x magnification are said to be 'IF' internally flawless.
    VVS1 / VVS2     very very small inclusions that are very hard to find
    VS1 / VS2        very small inclusions that are difficult to find
    SI1 / SI2        slight inclusions that can be found
    P1 / P2         inclusions that can be visible with the naked eye

Cut – Diamonds can be purchased in a variety of shapes ranging from round to square, oblong and even fancy heart shapes, but the cut of a diamond does not only refer to the overall shape of the stone but also to the facets (flat surfaces cut into the stone) and their arrangement. Some names of cuts include round brilliant, old cut, cushion, marquise and pendeloque.

Carat – This refers to the size of the diamond or to be more specific its weight. The only way to accurately measure a diamonds weight is to weigh it loose, however this is not always possible and it is often possible to take measurements of the stone whilst set to calculate an approximate weight.