What’s New With Cobalt?
Featured ArticlesBy now, we should all be aware of last years discovery of the use of cobalt coatings to improve the color of Tanzanite. This treatment, as reported by the AGTA-GTC and the AGL (May 23…
GemWorld articles are accessible by GemGuide members only. To access our archive of articles and get many other great features and benefits, become a member now!
Become a member