Hancockite

General Information:
 Chemical Formula:
(Pb,Ca,Sr)2(Al,Fe+++)3(SiO4)3(OH)
 Environment:
Metamorphosed zinc deposit.
 Locality:
Franklin, New Jersey
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
brown, brick red, brownish red, or maroon.
 Density:
4
 Diaphaniety:
Translucent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Striated - Parallel lines on crystal surface or cleavage face.,
 Hardness:
6-7 - Orthoclase-Quartz
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Dull
 Streak:
brownish white
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