Mackayite

General Information:
 Chemical Formula:
Fe+++Te2O5(OH)
 Composition:
(Molecular Weight = 408.05 gm)
Iron 13.69 % Fe
Tellurium 62.54 % Te
Hydrogen 0.25 % H 
Oxygen 23.53 % O 
 Empirical Formula:
Fe3+Te2O5(OH)
Physical Properties:
 Cleavage:
None
 Color:
brownish green, yellow green, or olive green.
 Density:
4.86
 Diaphaniety:
Transparent
 Hardness:
4.5 - Between Fluorite and Apatite
 Luster:
Vitreous (Glassy)
 Streak:
light green
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