thorium dioxide

chemical compound

Also known as: thoria

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Last updated

July 14, 2026

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Thorium dioxide, also known as thoria, is a refractory crystalline compound with the chemical formula ThO₂. It is typically obtained as a dense white powder. Thorium dioxide is a key component in incandescent gas mantles, crucibles, refractories, and silica-free optical glass. It is also used in catalysts and as a refractory material in high-temperature processes. Thorianite is a mineral form of thorium dioxide, known for its density and hardness. Thorium itself is a radioactive element that can be used as a nuclear reactor fuel.1234

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monazite
…monazite frequently contains 10–12 percent thorium dioxide (ThO₂) and thus represents a major commercial source of thorium as well. Countries in which monazite is mined include India, Malaysia, Vietnam, and Brazil. For detailed physical properties, see phosphate mineral (table).
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…monazite frequently contains 10–12 percent thorium dioxide (ThO₂) and thus represents a major commercial source of thorium as well. Countries in which monazite is mined include India, Malaysia, Vietnam, and Brazil. For detailed physical properties, see phosphate mineral (table).
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thorium processing
Thorium dioxide
The only other thorium compound of any industrial significance is ThO₂, known as thoria. For nuclear applications, thoria is prepared by calcination of thoroughly purified Th(NO₃)₄. Thoria also finds some application as a refractory material in various high-temperature processes.
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The only other thorium compound of any industrial significance is ThO₂, known as thoria. For nuclear applications, thoria is prepared by calcination of thoroughly purified Th(NO₃)₄. Thoria also finds some application as a refractory material in various high-temperature processes.
Read More