Chalcanthite

Chalcanthite, whose name derives from the Greek, chalkos and anthos, meaning copper flower, is a richly-colored blue/green water-soluble sulfate mineral, commonly found in the late-stage oxidation zones of copper deposits. Due to its ready solubility, chalcanthite is more frequently found in greater abundance in arid regions.
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Noun
1. hydrated blue crystalline form of copper sulfate
(synonym) blue vitriol, blue copperas, blue stone
(hypernym) copper sulfate, copper sulphate, cupric sulfate, cupric sulphate

(n.)
Native blue vitriol. See Blue vitriol, under Blue.
  

General Information:
 Chemical Formula:
CuSO4·5(H2O)
 Composition:
(Molecular Weight = 249.69 gm)
Copper 25.45 % Cu
Hydrogen 4.04 % H 
Sulfur 12.84 % S 
Oxygen 57.67 % O 
 Empirical Formula:
Cu(SO4)·5(H2O)
 Environment:
Secondary, formed in arid climates or in rapidly oxidizing copper deposits.
 Locality:
Walls and timbers of copper mines.
 Name Origin:
From the Greek chalkos, "copper" and anthos, "flower." Generally pysdomorphous after Boothite.
Physical Properties:
 Cleavage:
[110] Imperfect, [110] Indistinct, [111] Indistinct
 Color:
green, green blue, light blue, or dark blue.
 Density:
2.12 - 2.3, Average = 2.21
 Diaphaniety:
Subtransparent to translucent
 Habits:
Encrustations - Forms crust-like aggregates on matrix., Stalactitic - Shaped like pendant columns as stalactites or stalagmites (e.g. calcite)., Reniform - "Kidney like" in shape (e.g .. hematite).
 Hardness:
2.5 - Finger Nail
 Luminescence:
None.
 Luster:
Vitreous (Glassy)
 Streak:
white
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