It is a monoclinic mineral, but the typical form of occurrence is massive and clay-like with no macroscopic crystals.

The color varies from green to yellow.

It has a Mohs hardness of 4 to 5 and a specific gravity of 8.5 to 9.5, quite high for a nonmetallic mineral.

It was first described from Goldfield, Nevada in 1868, and later from the Schneeberg District, Ore Mountains, Saxony, Germany.

This article about a specific oxide mineral is a stub.