The distinction between emerald and green beryl is based primarily on which color property?

• A. Hue
• B. Color Intensity
• C. Saturation
• D. Transparency

Answer: (B)

Color intensity describes how deep and vivid the green appears in the stone. Emerald is essentially a green beryl with a strong, saturated green color, so the name goes to how intense that color looks under standard lighting. Hue—the general green family—stays similar for both stones, so it doesn’t distinguish them. Saturation refers to the purity of the color, but two stones can share similar purity yet differ in how strong the color appears; the perceived strength of the green is the practical criterion gemologists use to call a stone emerald rather than just green beryl. Transparency affects overall appearance but isn’t the factor that determines the color name.