New Blue Chart Is Available

The second edition of Blue Chart, a reference book for gem identification by Swiss gemologist Hervé Nicolas Lazzarelli (, has been published. It comes with eight double-wide pages of gemstone species and varieties, arranged from high to low refractive indices; a page of color-organized distinctive pleochroism reactions; three pages of classic spectrums for natural, treated, and synthetic gems; and two pages of gems ranked by specific gravities. It’s a useful all-purpose desk tool for gem identification. For more information, visit