Columbite-(Fe)
Etta Mine, Keystone, Keystone Mining District, Pennington County, South Dakota, USA
7.7 x 4.7 x 4.4 cm
A very good sized, sharp, lustrous, deep black, blocky, prismatic crystal of Columbite-(Fe) from the Etta Mine in the Keystone District of South Dakota. This crystal sits on a small amount of feldspar matrix. From the collection of John Arnaud, formerly of Westcliffe, Colorado.
© Brian Kosnar - Mineral Classics