Among the most treasured minerals in the world of gemstones, corundum stands out for its exceptional hardness, brilliance, and remarkable color diversity. Cherished by artisans, collectors, and traders alike, its color alone determines not only its name but also its value. When corundum appears in red, it is known as ruby; in blue, it becomes sapphire. Even a subtle variation in hue can significantly influence a gem’s market price.

To establish a unified and transparent standard for color assessment, the Gem and Jewelry Institute of Thailand (GIT) has developed the “GIT Standard Color Reference for Corundum.”

This color grading system provides a reliable benchmark for gemstone identification and certification — ensuring accuracy, consistency, and global confidence in the Thai gem and jewelry industry.