corundum, USA.12, Montana.12, gems

Intergem Inc. of Aurora, Colorado, pres-ently owns the sapphire deposit in Yogo Gulch, Mon-tana. In 1983,the mine produced approximately 200,000 ct of sapphire in limited surface mining. (Thepercentage of this material that was of cuttable gem quality was not reported.)Once it has completed careful exploration, the company plans to put the mine into full operation.