我的理解是，因为前两个是小于10克拉的，第三个上十克拉。引用证书原话是：“The described gemstone exhibits a vivid blue color combined with a fine purity and an attractive cutting style...A natural sapphire from Kashmir of this size and quality is rare and exceptional." 切得比较中规中矩，没有大屁股，没有明显包体，颜色饱和度高。