Torbernite, whose name derives from the Swedish chemist Torbern Bergman, hydrated green copper uranyl phosphate , 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 Cu2+ cation replaces a Ca2+. 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(UO2)2(PO4)2 • 12H2O Metatorbernite Cu(UO2)2(PO4)2 • 8H2O
Torbernite's most common alternative names are copper uranite and cupro-uranite.