Cut

"If a diamond is properly cut, it should capture and throw back as much light as possible giving it that beautiful sparkle. If the proportions of a diamond are too deep or too shallow, light can be lost. Don’t lose that dazzle."

Cut is the only element of the 4Cs that is not brought about by natural conditions.

However, it is regarded by some experts as the most crucial of the 4Cs. It refers principally to the quality of the diamond's cut, and not the size or shape (even though these can be interchangeable), and to what standard the diamond is faceted, proportioned, and polished.

A ‘good’ diamond that is poorly cut is essentially ruined. On the other hand, a less valuable diamond cut with expert skill can become more appealing and valuable.

Cut affects how the diamond interacts with light. Brilliance, which is a term used to describe a stone's ability to return light to the naked eye, is assessed solely by the stone's cut. Colour and clarity have no relevance here.

For any diamond shape, cut is the first C to ponder. Next is colour, then clarity - assuming the stone features no visible imperfections.

Under the established GIA (Gemological Institute of America) system, diamond cuts are graded under Excellent, Very Good, Good, Fair, and Poor. What’s interesting is that cut grade doesn't usually affect the cost of the stone to the same extent as the other Cs.

Most diamonds are cut round, with a full 58 facets. A high quality cut gives more sparkle.

Experts generally recommend staying within the Excellent to Very Good range if you’re looking for a quality cut that works well with light. Any range of colour and eye-clean clarity is guaranteed to be striking and extremely bright, as long as the diamond is well cut.