Haiweeite

General Information:
 Chemical Formula:
Ca(UO2)2[Si5O12(OH)2]·4.5(H2O)
 Composition:
(Molecular Weight = 1,078.71 gm)
Calcium 3.72 % Ca
Uranium 44.13 % U 
Silicon 15.62 % Si
Hydrogen 0.93 % H 
Oxygen 35.60 % O 
 Empirical Formula:
Ca(UO2)2Si6O15·5(H2O)
 Environment:
Secondary, oxidation product.
 IMA Status:
Approved IMA 1959
 Locality:
Haiwee Reservoir, Inyo Co. California.
 Name Origin:
Named after it's locality.
Physical Properties:
 Cleavage:
[001] Good
 Color:
greenish yellow or light yellow.
 Density:
2.86 - 3.35, Average = 3.1
 Habits:
Microscopic Crystals - Crystals visible only with microscopes., Spherical - Spherical, rounded aggregates., Aggregates - Made of numerous individual crystals or clusters.
 Hardness:
3.5 - Copper Penny
 Luster:
Pearly
 Streak:
white
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