Haynesite

General Information:
 Chemical Formula:
(UO2)3(SeO3)2(OH)2·5(H2O)
 Composition:
(Molecular Weight = 1,188.09 gm)
Uranium 60.10 % U 
Hydrogen 1.02 % H 
Selenium 13.29 % Se
Oxygen 25.59 % O 
 Empirical Formula:
(UO2)3(SeO3)2(OH)2·5(H2O)
 Environment:
Found as crusts on mudstones and sandstones of the Morrison formation.
 IMA Status:
Approved IMA
 Locality:
Repete mine near Blanding, San Juan County, Utah. USA.
 Name Origin:
Named for Patrick Haynes, U.S. Geologist who first collected the mineral.
Physical Properties:
 Cleavage:
[010] Good
 Color:
brownish yellow or amber.
 Density:
4.1
 Diaphaniety:
Transparent to Translucent
 Habits:
Tabular - Form dimensions are thin in one direction., Acicular - Occurs as needle-like crystals., Rosette - Bundled tabular aggregates resembling rose flower petals.
 Hardness:
1.5-2 - Talc-Gypsum
 Luminescence:
Fluorescent, Short UV=yellowish green.
 Luster:
Vitreous (Glassy)
 Streak:
white
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