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A highly radioactive blackish, greenish, or yellow mineral, ThO2, isomorphous with uraninite.

[thoria + -an + -ite.]


(Minerals) a rare black mineral consisting of thorium and uranium oxides. Formula: ThO2.U3O8


(ˈθɔr i əˌnaɪt, ˈθoʊr-)

a rare, black, radioactive mineral, mainly thoria, ThO2, usu. found mixed with uranium, dioxide, and rare-earth metals: a minor source of thorium.
[1900–05; thorian (thori (a) + -an2) + -ite1]
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The great thorium in monazite precautions are in India, USA, Australia, Norway and Russia; and also, not exploited until now, in Canada in the form of urano thorianite (Salinas-Pedroza and Olguin, 2004).
has perhaps the world's largest mineable deposit of the primary thorium minerals, thorite and thorianite.
It must be noted that the Idaho and Montana deposits are of high-grade thorite and thorianite rather than low-grade disseminated deposits as in India, for example.