Diamonds and light

Why does a diamond sparkle differently in daylight compared to artificial light?

Al Gilbertson, a researcher in the GIA laboratories, suggests that we look at a diamond as being a series of small mirrors that reflect their environment. When you look at your diamond, the whole of your environment, including yourself, is reflected inside the stone. If you move the stone further away and bring it gradually towards your eye, the closer the diamond gets, the more a slightly dark area appears in the stone: it’s your reflection!

The way in which a stone sparkles is mainly dependent on the quality of the cut. The cut is one of the 4 characteristics (4Cs – colour, clarity, carat, cut) that bring out the beauty and value of a stone. It’s also the least understood as its value is the result of a combination of several characteristics. It is defined as excellent, very good, good, fair and poor. Each term refers to a combination of all these characteristics. There is no ideal combination: several proportions may, for example, lead to a very good value on a certificate.

Of course, all these characteristics are the result of a detailed laboratory study carried out by professionals using the very latest equipment. When you buy a diamond, you don’t have access to these types of tools. So how do you go about assessing the beauty of a diamond? Firstly, observe the diamond in the environment in which it will be most often worn, probably under artificial light. Trust your judgement and don’t be afraid to choose the stone that attracts you most. Your jeweller will obviously be able to offer invaluable advice. Finally, the certificate that accompanies the stone, generally GIA or HRD (Hoge Raad voor Diamond), will provide you with a very precise identity card for the jewel.

Come and see us if you’d like to know more about the characteristics of a diamond.