Sodalite Enlarge
Mar 1 1812 published by Jas Sowerby London.
Exotic Mineralogy
XL
Silex

Sodalite

  • Syn. Sodalite. Thompson in Trans. of the Royal Society of Edinburgh, 1811.

Mr. Allan, some time ago, obtained, from on board a Danish prize, a collection of minerals supposed to be from Greenland, among which were several specimens of the present substance. As they exhibited peculiar characters, they were distributed, among other friends, to Dr. Thompson and Mr. Ekeberg, who, having analysed it, showed it to be new. Dr. Thompson also described and named it. It occurs in a rock supposed to be primitive, mixed with Sahlite, Augit, Hornblende, and Garnet, and is either massive, or crystallized in rhomboidal dodecaëdrons (see the lower, middle, and right hand figures) which in some cases are lengthened, forming six-sided prisms, terminated by triëdral pyramids. The colour a rather pale, dull, bluish green. It yields with difficulty to the knife. The Spec. Grav. according to Dr. Thompson, is 2.378; and is infusible by the blow-pipe, but becomes of a dark grey.

Analysis by Dr. Thompson By Mr. Ekeberg.
Silica 38.52 36.00
Alumina 27.48 32.00
Lime 2.70
Oxide of Iron 1.00 0.25
Soda 23.50 25.00
Muriatic Acid 3.00 6.75
Volatile matter 2.10
Loss 1.70
100.00 100.00
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