Ferberite-huebnerite Series

Ferberite crystals on granitic matrix, from the McGuire Pit, Marathon County, Wisconsin. Field of view is 1.5 mm left to right. (Image courtesy Dan Behnke, specimen collected by Dan Behnke.)

Formula: (Fe,Mn)WO4 – Monoclinic

Description:

The ferberite-huebnerite series is a series of tungstate minerals with varying proportions of iron to manganese. They are relatively high temperature minerals characteristically found in quartz veins associated with granite.

MARATHON COUNTY: Both ferberite and huebnerite have been reported associated with topaz, cassiterite and other rare minerals from the McGuire Pit, west of Wausau. The ferberite-huebnerite form “dark red-brown to black crystals to 1.5 mm on and in albite and quartz”.(Buchholz et al., 2004).