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Stützite

Stützite
Stutzite-Tellurium-169921.jpg
Stützite from the Moctezuma Mine, Sonora, Mexico (size:3.7 x 3.3 x 1.7 cm)
General
Category Telluride mineral
Formula
(repeating unit)
Ag5−xTe3(with x = 0.24 to 0.36)
Strunz classification 2.BA.30e
Crystal system Hexagonal
Crystal class Dihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Space group P6/mmm
Unit cell a = 13.38, c = 8.45 [Å]; Z = 7
Identification
Color Dark lead-gray
Crystal habit Massive, compact, granular
Cleavage None observed
Fracture Subconchoidal
Tenacity Brittle
Mohs scale hardness 3.5
Luster Metallic
Diaphaneity Opaque
Specific gravity 8.0
Alters to Tarnishes rapidly to a dark bronze to iridescence
Other characteristics Anisotrpism in polished section: Moderate, in gray reddish brown-blue
References

Stützite or stuetzite is a silver telluride mineral with formula: Ag5−xTe3 (with x = 0.24 to 0.36) or Ag7Te4.

It was first described in 1951 from a museum specimen from Sacarimb, Romania. It was named for Austrian mineralogist Xavier Stütz (1747–1806).

It occurs with other sulfide and telluride minerals in hydrothermal ore occurrences. Associated minerals include sylvanite, hessite, altaite, petzite, empressite, native tellurium, native gold, galena, sphalerite, colusite, tennantite and pyrite.



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