The Rare Earths: Their Occurrence, Chemistry, and Technology

by Stanley Isaac Levy

In the alphabetical [list], particulars of the following rare earth phosphates will be found:

Castelnaudite, a variety of xenotime containing zirconia.

Churchite and Rhabdophane (Scovillite), hydrated phosphates.

Gorceixite, an alumino-phosphate of alkaline and ceria earths.

Retzian, an hydrated arsenate of manganese, calcium and rare earth metals.

(b) The Halides

Yttrocerite.

—This mineral is a fluoride of calcium and rare earth metals, with water. A recent analysis by Tschernik[116] gives the formula Ce₂F₆,2Y₂F₆,9CaF₂,2H₂O. Putting the rare earth metals together, this gives 6RF₃,9CaF₂,2H₂O, or R₂Ca₃F₁₂,²⁄₃H₂O. Yttrocerite is of interest since it was probably in the analysis of this mineral by the discoverers, Berzelius and Gahn, that the double sulphate method of separating the yttria from the ceria earths was first employed[117] (vide [p. 156]).

[116] Abstr. Chem. Soc. 1907, 92, ii. 362.

[117] Schweigg. J. 1816, 16, 244.