Did you know why the diamond colour grading system starts with D?
Before the GIA colour grading system, there were many different colour grading systems used by diamond traders.
It could be letters of the alphabet, A, AA, AA, A, B or C. With multiple AAAA’s as the best stone. Arabic 0.1.2.3And Roman numerals I, II, III
Diamonds were also described such “river” and “water” for the most colourless diamonds, and sometimes they were categorized by a geographic location from places where similar coloured diamonds were seen. For instance, were “Cape” for pale yellow diamonds from the Cape of Good Hope.
So it was super confusing and very inconsistent and inaccurate to compare and determine diamond colour.
American Gem Society ( AGS) had its own scale, only for AGS numbers, so when GIA (Gemological Institute of America) took matters into their own hand, they had to use new terms, Hence the D. D represents colourless and continues with the increasing presence of colour to the letter Z.