OVERVIEW OF TANTALUM
Tantalite ≤86% Ta 2 O 5 and Columbite ≤78% Nb 2 O 5 Orthorhombic stunted tabular or slender striated, radiating crystals Opaque, black to grey to brown, sub-metallic to -resinous lustre and dark red to black streak SG 5.3 columbite to 7.8 tantalite. Brent Barber - …