- a rare mineral, mainly thoria, ThO2, but also containing uranium, cerium, and other rare-earth metals, occurring in small, black, cubic crystals: notable for its radioactivity and used as a minor source of thorium.
Origin of thorianite
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Examples from the Web for thorianite
The richest known source is thorianite, which consists mainly of thorium oxide, and contains 9.5 cc.
Much the best practical source of helium is thorianite, a mineral imported from Ceylon for the manufacture of thoria.
- a rare black mineral consisting of thorium and uranium oxides. Formula: ThO 2 .U 3 O 8
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