Читать книгу The Rare Earths: Their Occurrence, Chemistry, and Technology - Stanley Isaac Levy - Страница 107

A variety of Samarskite (q.v.) containing Pb; R´´₂Cb₂O₇, R´´´₄(Cb₂O₇)₃, where R´´ = Fe, Pb, Ca, UO, R´´´ = E, Al. Yttr = 14·3%.

Massive, isotropic.

G = 4·80-4·81. H = 5-5¹⁄₂. Dark brown to black.

Morogoro, Uluguru Mountains, German E. Africa.