A mineralogical study of pyrochlore and betafite.

Pyrochlore has been found in many localities and promises to be an important source of niobium. Betafite is also widespread in occurrence and has been mined intermittently in Madagascar as a minor uranium ore; in other localities it does not seem to occur in economic quantities. Although several independent studies of betafite and pyrochlore have been undertaken, the relationship of the one mineral to the other is not clear. The X-ray powder patterns of pyrochlore and ignited betafite are very similar although usually not identical. However, the chemical compositions are quite different