• Webster's Revised Unabridged Dictionary
    • n Thoria (Chem) A rare white earthy substance, consisting of the oxide of thorium; -- formerly called also thorina.
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Century Dictionary and Cyclopedia
    • n thoria The name was first given by Berzelius to a supposed new earth announced by him in 1815 as present in xenotime and other Swedish or Norwegian minerals. He afterward proved that this material was in fact yttrium phosphate. In 1828 he discovered a really distinct earth in tine mineral thorite, and applied to it the same name (from the god Thor of Scandinavian mythology), and in this sense the word is used. This earth the oxid of thorium, forms the principal part of the mautles of Welsbach incandescent gas-lamps The material used has been varied, with a view to securing as white a light as possible, but is said to be commonly about 99 per cent. of thorium oxid and 1 per cent of cerium oxid.
    • n thoria An oxid of thorium, ThO2. When pure it is a white powder, without taste, smell, or alkaline reaction on litmus. Its specific gravity is 9.4. It is insoluble in all acids except sulphuric.
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Webster's Revised Unabridged Dictionary
NL. See Thorite


In literature:

We are told that Ber fell in this combat, while Thorias left the battle severely wounded.
"The Danish History, Books I-IX" by Saxo Grammaticus ("Saxo the Learned")
The specific gravity of pure thoria is 10.2207 to 10.2198.
"Scientific American Supplement, No. 365, December 30, 1882" by Various
Much the best practical source of helium is thorianite, a mineral imported from Ceylon for the manufacture of thoria.
"Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 2" by Various
With thoria the shrinkage is smaller than with any other known substance, and it possesses very high refractory powers.
"Encyclopaedia Britannica, 11th Edition, Volume 16, Slice 6" by Various