Yecoraite

General Information:
 Chemical Formula:
Bi5Fe+++3(Te++++O3)(Te++++++O4)2O9·9(H2O)
 Composition:
(Molecular Weight = 1,933.37 gm)
Iron 8.67 % Fe
Bismuth 54.05 % Bi
Tellurium 19.80 % Te
Hydrogen 0.94 % H 
Oxygen 16.55 % O 
 Empirical Formula:
Bi5Fe3+3(TeO3)(TeO4)2·9(H2O)
 Environment:
Oxidation of tetradymite and pyrite.
 IMA Status:
Approved IMA
 Locality:
Yecora, Sonora, Mexico.
 Name Origin:
Named for the locality.
Physical Properties:
 Color:
yellow, resin yellow, or orange.
 Density:
5.59
 Habits:
Cryptocrystalline - Occurs as crystals too small to distinguish with the naked eye., ,
 Hardness:
3 - Calcite
 Luminescence:
Non-fluorescent.
 Luster:
Resinous
 Streak:
yellow
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