The Rare Earths: Their Occurrence, Chemistry, and Technology

by Stanley Isaac Levy

Na₂Zr(Si₂O₅)₃, 1¹⁄₂H₂O. ZrO₂ = 20·5%.

Orthorhombic.

G = 2·52-2·56. H = 7-8. Colourless to red; translucent.

Various localities in Greenland.

Endeiolite.

R´´Cb₂O₆(OH)₂ + R´´SiO₃ (cf. [Chalcolamprite]). E₂O₃ = 4·43; ZrO₂ = 3·78%.

Cubic.

G = 3·44. H = 4. Dark chocolate-brown; transparent.

Narsarsuk, Greenland.

Erdmannite (Michaelsonite).