GUlLD ldentification and Grading Standard of Emerald

Emerald is the green variety of berylfamily, mainly containing chromium and /or vanadium as the color agent. In GuildGem Laboratories, we have created ourown Color Master Set as a standard foraccurate and repeatable grading resultsfor emeralds. In terms of hue, tone andsaturation, the color of emeralds can beclassified into five grades: Light/Medium/Intens/Vivid-Verdant Green/Deep