INTRODUCING THE 4C’S

The 4Cs are a universally recognised method for assessing the quality of any type of diamond, anywhere in the world. Being chemically and physically identical, both lab grown and mined diamonds are graded in this way. The 4C’s stand for cut, clarity, colour and carat.

The 4Cs were developed in the early 1940s by GIA (Gemological Institute of America) founder Robert M. Shipley. A former retail jeweller, Shipley was a great advocate for professionalising the industry. He came up with the 4C’s as a way for his students to remember the characteristics of a faceted diamond. The concept was simple, but revolutionary as previously diamond merchants had used inconsistent terms which made it difficult for jewellers to communicate elements of value to their customers. Only the term carat to describe weight has been used consistently since the 1500s.

CLARITY

The clarity of a diamond references the purity of the stone. The clearer it is, the higher grade it possesses. Determining diamond clarity involves evaluating the number, size, relief, nature and position of these characteristics, as well as how these affect the overall appearance. The diamond’s growth process can result in internal characteristics called ‘inclusions’ and external ones called ‘blemishes’.

COLOUR

The evaluation of colour is actually based on the absence of colour. A chemically pure and structurally ‘perfect’ diamond has no hue, which gives it a much higher value. Although we tend to think of diamonds as colourless, they range from yellow and brown to grey. There are also ‘fancy coloured’ diamonds but they go off this colour scale as they have a distinct and opulent colour and are valued for their intensity.

CARAT

The carat is the measurement of how much a diamond weighs and is a universal measurement. Several factors affect the weight of a stone, including density, formulation and shape. Total Carat Weight or TCW represents the total weight of all diamonds or other gemstones in a piece of jewelry, when more than one stone is used. 

Fun fact: the term carat comes from the carob seed as in the past gem merchants used carob seeds to help weigh gemstones and diamonds because the seeds were uniform in weight and size.

CUT

The cut grade is about how well the stone’s facets interact with light. Precise workmanship is required to prepare a diamond, so its proportions, symmetry and polish deliver a brilliant reflection of light.The better a diamond has been cut, the greater the diamond’s ability to reflect and refract light.