Читать книгу The Rare Earths: Their Occurrence, Chemistry, and Technology - Stanley Isaac Levy - Страница 66

3H₂0, 2R´´O, 3R´´´₂O₃, 4SiO₂, where R´´ = Ca, Mg, Th 2; R´´´ = E, Al, Fe, Mn. E₂O₃ = 40%.

Monoclinic; habit prismatic.

G = 3·70. H = 5¹⁄₂. Reddish-brown when fresh.

Lindvikskollan and Kragerö, Norway.