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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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References in periodicals archive ?
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).
Summary: Thorium, the radioactive metal, present in natural sediments produced in the form of detritus minerals such as monazite, rutile, granitic complexes, syenitic complexes, thorite, thorianite and progenitor of U, Th and Ac series.
Associated minerals are: dolomite, fluororichterite, chromite, thorianite, forsterite and phlogopite.