Tanzanite grading reports are now offered by the American Gem Trade Association (AGTA) Gemological Testing Center (GTC) in cooperation with the Tanzanite Foundation.

The reports are in accordance with the Tanzanite Quality Scale, a tanzanite-specific grading system launched in North America in March 2007 and Hong Kong in September 2007.

The Tanzanite Quality Scale grades according to specific standards under the 4C’s criteria of carat, color, clarity and cut.

The Tanzanite Foundation’s aim is to establish a universal system for grading of the stone so as to facilitate trade and increase consumer confidence and encourage the development of a more formalized industry.