Columbite-(Fe) – New Mexico, USA
Weight: 68.4 g
Size: 46x35x25mm
Locality: Petaca Mining District, Rio Arriba County, New Mexico, USA
Formula: FeNb₂O₆
Columbite-(Fe) is an iron-dominant niobium oxide mineral of the columbite–tantalite group, typically forming black to dark brown prismatic crystals with a submetallic luster. It occurs mainly in granitic pegmatites and is an important ore of niobium.
65-75% Niobium by mass
XRF analysis performed by Charles David Young, who also numbered the bottom of the specimen.
