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Russian Gemstones Encyclopedia

Vladimir Bukanov. Russian Gemstones Encyclopedia

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TUGTUPITE


TUGTUPITE (Tugtupit—Tugtupite—“угтупит) (Sörensen, H. 1962), after its discovery location at Tugtup Agtakôrfia, the Ilimaussaq alkali complex, Greenland. Silicate – Na4[Cl|BeAlSi4O12], subclass framework silicate, tetragonal system. Hardness 6. Density 2.2-2.5. Glass luster. Color: light pink, violet-red, sometimes with or light bluish. It displays clear pleochroism from violet-red to orange-red. Its color depends on the admixture of ions of sulfur (S22-), because of the quantity of which its intensity varies. Under direct light its color gets pale after some time. Translucent to non-transparent. In long-waved ultra-violet rays for tugtupite bright violet-red fluorescence is typical; in short-waved ultra-violet rays it is rose-orange. Tugtupite is a rare mineral, which is found mainly in fine-grained masses and extremely rarely in the form of columnar crystals. Tugtupite in the form of rose-white fine-grained aggregates for the first time was discovered in South Greenland, in the Ilímaussaq alkali complex, in 1960 . There, on the Kvanefjeld Plateau, in albite veins, they found massive translucent violet-red tugtupite; and near Narsaq Field – light blue one. In Russia, tugtupite was discovered in pegmatites of alkali rocks on the Kola Penin., in the Khibiny massif – in the Eveslogchorr Mt.; and in the Lovozero massif – at the Umbozero mine, Alluaiv Mt., in the form of accumulations up to 3x5 cm. in size as an alteration product of chkalovite. In Canada, ornamental tugtupite is found in the Québec Prov., at the Mont St Hilaire massif.

Translucent violet-red tugtupite is faceted. Massive varieties are used in stone-carving; they are also cut in cabochons and for beads.

Synonyms. Beryllosodalite | Rentierstein, Germ. | Deer stone.

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