Читать книгу The Rare Earths: Their Occurrence, Chemistry, and Technology - Stanley Isaac Levy - Страница 97

Na₆FeTi₂Si₁₂O₃₂F. TiO₂ = 14%.

Tetragonal. Habit tabular.

Gr = 2·75. H = 7-7¹⁄₂. Yellow to reddish-brown; pleochroic.

Plain of Narsarsuk, Greenland.