RECOVERY OF THORIUM FROM ORES IN COLORADO, IDAHO, AND MONTANA

An investigation was made of the extractive metallurgy of thorite ores. The work was done mainly on thorite ore containing 3.87% ThO/sub 2/ from the Powderhorn district of Colorado and on a composite sample containing 0.52% ThO/ sub 2/ from the West Mountains district of Colorado. Limited tests of a corroborative nature were also made on a sample containing 2.30% ThO/sub 2/ from the Lemhi Pass area on the Idaho-Montana border. Procedures examined by batch and continuous bench-scale tests are described. It was concluded that domestic thorite ores of the type examined are amenable to treatment by an acid leach solvent extraction process. Over 90% of the Th is readily recoverable in a product containing about 99% ThO/sub 2/. (C.H.)