本文件规定了0.25克拉（ct）以上单颗未安装抛光钻石分级和描述所用的术语、分类和方法。 本文件适用于天然、未安装、抛光钻石。不得用于彩色钻石、合成钻石、处理过的钻石（7.4中允许的除外），也不得用于组装钻石。

This document specifies the terminology, classification and the methods that are used for the grading and description of single unmounted polished diamonds over 0,25 carat (ct). This document applies to natural, unmounted, polished diamonds. It is not to be used for fancy coloured diamonds, synthetic diamonds, treated diamonds (other than is allowed for in 7.4), nor for assembled stones.