Restudy of type elpasolite of Cross and Hillebrand (1885) proves it to be a species distinct from cryolite and identical with artificial K2NaAlF6. Isometric, simple cell, with a0 = 8.093 and cell contents K8Na4Al4F24 Hardness 2½ specific gravity 2.995 (obs.), 3.015 (calc.). No cleavage, fracture uneven. Colorless, with the luster of cryolite. Isotropic, with n = 1.376 ± 0.002.

Hagemannite of Shepard (1866) from Ivigtut is shown to be a variable mixture of ralstonite and thomsenolite pigmented with iron oxide.

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