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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Historical Examples of 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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