Caledonite

Caledonite, whose name derives from Caledonia, the historical name of its place of discovery (Scotland), is a richly colored blue-green sulfate mineral with an orthorhombic crystal structure, commonly found in the oxidized zones of copper-lead deposits as a secondary mineral.
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(n.)
A hydrous sulphate of copper and lead, found in some parts of Caledonia or Scotland.
  

General Information:
 Chemical Formula:
Pb5Cu2(CO3)(SO4)3(OH)6
 Composition:
(Molecular Weight = 1,613.34 gm)
Copper 7.88 % Cu
Hydrogen 0.37 % H 
Lead 64.21 % Pb
Carbon 0.74 % C 
Sulfur 5.96 % S 
Oxygen 20.83 % O 
 Empirical Formula:
Pb5Cu2(CO3)(SO4)3(OH)6
 Environment:
Secondary, weathered zone of lead and copper ores.
 Locality:
Mammoth Mine at Tiger, Arizona.
 Name Origin:
Named after Caledonia, the historical name of Scotland.
Physical Properties:
 Cleavage:
[001] Perfect, [100] Distinct
 Color:
blue, blue green, green, or dark green.
 Density:
5.7 - 6.4, Average = 6.05
 Diaphaniety:
Transparent to Translucent
 Habits:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Striated - Parallel lines on crystal surface or cleavage face.
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luminescence:
None.
 Luster:
Vitreous - Greasy
 Streak:
greenish white
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