Stützite

Stützite or stuetzite is a silver telluride mineral with formula: Ag5−xTe3 (with x = 0.24 to 0.36)[1] or Ag7Te4.[4]

Stützite
Stutzite-Tellurium-169921.jpg
Stützite from the Moctezuma Mine, Sonora, Mexico (size:3.7 x 3.3 x 1.7 cm)
General
CategoryTelluride mineral
Formula
(repeating unit)		Ag5−xTe3 (with x = 0.24 to 0.36)
Strunz classification2.BA.30e
Crystal systemHexagonal
Crystal classDihexagonal dipyramidal (6/mmm)
H-M symbol: (6/m 2/m 2/m)
Space groupP6/mmm
Unit cella = 13.38, c = 8.45 [Å]; Z = 7
Identification
ColorDark lead-gray
Crystal habitMassive, compact, granular
CleavageNone observed
FractureSubconchoidal
TenacityBrittle
Mohs scale hardness3.5
LusterMetallic
DiaphaneityOpaque
Specific gravity8.0
Alters toTarnishes rapidly to a dark bronze to iridescence
Other characteristicsAnisotrpism in polished section: Moderate, in gray reddish brown-blue
References[1][2][3]

It was first described in 1951 from a museum specimen from Sacarimb, Romania. It was named for Austrian mineralogist Xavier Stütz (1747–1806).[1][2]

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. 


This article uses material from the Wikipedia article
 Metasyntactic variable, which is released under the 
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