Feature
Gems & Gemology, Spring 1994, Vol. 30, No. 1
The Indaia Sapphire Deposits of Minas Gerais, Brazil
David S. Epstein, Warren Brennan, and Julio C. Mendes
The discovery of significant quantities of gem-quality sapphire in Minas Gerais could add corundum to the formidable list of gem species already commercially produced in Brazil. The presence of sapphire has been confirmed over a wide area within a 42-km2 mining claim, and exploration has yielded over 500 ct of corundum per square meter from alluvium in a small section of the claim. Faceting-quality stones typically range from 0.5 to 2ct; some are purple or violet, and many show a color change. Future production will depend primarily on the results of ongoing exploration and the feasibility of mechanizing an area of difficult access.