The American Gem Trade Association (AGTA) has taken the initiative to offer tanzanite grading reports at its Gemological Testing Center. The grading is in accordance with the tanzanite quality scale developed by the Tanzanite Foundation. The scale has been launched in North America in March 2007 and Hong Kong in September 2007. The grading categorises according to specific standards under the 4 C’s criteria.

AGTA’s grading certificates will authenticate the stone’s natural origin from the world’s only known tanzanite source of Mount Kilimanjaro in Tanzania. In 2002, the AGTA selected tanzanite as a December birthstone.