Emmonsite

General Information:
 Chemical Formula:
Fe+++2Te++++3O9·2(H2O)
 Composition:
(Molecular Weight = 674.52 gm)
Iron 16.56 % Fe
Tellurium 56.75 % Te
Hydrogen 0.60 % H 
Oxygen 26.09 % O 
 Empirical Formula:
Fe3+2Te3O9·2(H2O)
Physical Properties:
 Cleavage:
[010] Perfect
 Color:
yellow or greenish yellow.
 Density:
4.52 - 4.53, Average = 4.52
 Diaphaniety:
Transparent to Translucent
 Habits:
Mammillary - Larger "breast-like" rounded forms resembling botryoidal (e.g. malachite)., ,
 Hardness:
2-2.5 - Gypsum-Finger Nail
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Dull
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