What is "torbernite"

Torbernite \Tor"bern*ite\, n. [So named after Torber Bergmann, a Swedish chemist.] (Min.) A mineral occurring in emerald-green tabular crystals having a micaceous structure. It is a hydrous phosphate of uranium and copper. Called also copper uranite, and chalcolite.

n. (context mineralogy English) A radioactive green phosphate mineral, isostructural with autunite, found in granites and other uranium-bearing deposits as a secondary mineral.

Not to be confused with Tobermorite, a Calcium Silicate Hydrate (CSH), one of the main constituents of cement paste. Not to be confused with Torbanite, also known as boghead coal, a variety of fine-grained black oil shale.

Torbernite, whose name derives from the Swedish chemist Torbern Bergman (1735–1784), is a radioactive, hydrated green copper uranyl phosphate mineral, found in granites and other uranium-bearing deposits as a secondary mineral. Torbernite is isostructural with the related uranium mineral, autunite.

The chemical formula of torbernite is similar to that of autunite in which a Cu cation replaces a Ca. The number of water hydration molecules can vary between 12 and 8, giving rise to the variety of metatorbernite when torbernite spontaneously dehydrates. Their respective chemical compositions are the following:

Torbernite

Cu(UO)(PO)·12 HO

Metatorbernite

Cu(UO)(PO)·8 HO

Torbernite's most common alternative names are copper uranite and cupro-uranite.