Natural-Color D-to-Z Diamonds: A Crystal-Clear Perspective

GEMS & GEMOLOGY FALL 2020 When people hear the word diamond, colorless diamonds generally come to mind— not the more exotic colors discussed earlier in this article series. In purchasing a diamond, they are likely to choose one that is colorless to nearcolorless. When one thinks of perfection in a diamond, a D-Flawless stone is usually the benchmark. The lack of color, which so inhibits the consumer appeal of many other gemstones, is instead considered a measure of stature for diamonds. Therefore, we finish this series (Breeding et al., 2018, 2020; Eaton-Magaña et al., 2018a, 2018b, 2019) by examining diamonds with very little to no color at all—those on the D-to-Z grading scale. Although they make up by far the largest proportion of stones submitted to GIA, detailed statistics of D-to-Z diamonds have never been presented before. In each of our previous colored diamond articles, we presented data on stones submitted to GIA from 2008 to 2016. For example, GIA examined more than 15,000 naturally colored blue/gray/violet diamonds in that period (Eaton-Magaña et al., 2018a). During those same years, GIA received millions of D-to-Z diamonds (e.g., figure 1). For this study, we examined all D-to-Z diamonds submitted for grading reports or dossier reports to any of GIA’s laboratories during much of 2017. From our analysis of submissions over the last decade, those from 2017 and used in this study are representative of GIA’s current and historical intake. Any diamonds submitted on multiple occasions during this period were identified, and only the most recent data for each stone are included in this study.