Diamond grading; why does it start with the D?

Diamond Grading

Typically, diamond grading begins with D and ends at Z. Now you may be asking, what is wrong with the good old A,B,C? Were those three letters that kick of that catchy tune we all know as the alphabet song just not good enough for the diamond graders?

Well don’t despair! They were once in the mix and if you are able to source yourself a diamond that predates 1940 you may be lucky enough to come across a diamond graded A-C.

Prior to the development of the Gemmological Institute of America (GIA) a uniform grading system for diamonds was not in place. Historically, metaphoric terms such as ‘river’ or ‘water’ were used to describe colourless diamonds. Coloured diamonds were also loosely graded and were largely described by the region from which they came. For instance, a pale yellow stone could be called a cape in reference to Cape River, the region from which it was from.

In later years the American Gemmological society (AGS) employed a numerical scale to grade its diamonds and some other institutions adopted an A-C system. However, the combination of competing standards and differentiation in terms meant the grading system was very confusing.

Luckily, The GIA, which was founded in 1940, wanted to develop a strong, uniform grading system that could be applied to diamonds universally. The GIA chose to do away with A,B,C. They started a fresh and chose the less commonly used D.

Since its conception the GIA has developed into the world’s leading diamond grading authority. While other grading bodies exist the GIA grading scale has been universally adopted. You will likely find that you can walk into any jewellery store in the world and the retailer will refer to the diamond grade in accordance with the GIA scale.

So while you may be sad that you can’t get an A grade diamond, it’s not as bad as it might seem. Diamond grading starting with the D was purposely done for the purpose of uniformity.

(*Even though grading terms are universal, grading definitions are not! click here to find out more)

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