It may be obtained as jet black octahedra (isomorphous with thoria) by fusion with borax.
The name thoria (after the Scandinavian god Thor) was first given in 1815 by Berzelius to a supposed new earth which he had extracted from several rare Swedish minerals.
In 1828 he gave the name thoria to an earth which he extracted from a mineral found at Lerdn.
Thorium chloride, ThC1 4, is obtained as white shining crystals by heating a mixture of carbon and thoria in a current of chlorine.
Rend., 1908, 147, p. 1046) obtains it by heating thoria in a current of carbonyl chloride.
In a somewhat impure condition it may be obtained by the reduction of vanadium pentoxide with a mixture of the rare earth metals which are obtained by reduction of the waste oxides formed in the manufacture of thoria (Weiss and Aichel, Ann., 1904, 337, p..