General Information:
Chemical Formula:
Cu4Al2(SO4)(OH)12·2(H2O)
Composition:
(Molecular Weight = 644.33 gm)
Aluminum 8.38 % Al
Copper 39.45 % Cu
Hydrogen 2.50 % H
Sulfur 4.98 % S
Oxygen 44.70 % O
Empirical Formula:
Cu4Al2(SO4)(OH)12·2(H2O)
IMA Status:
Accepted IMA 1961
Name Origin:
From the Greek, kyaneos, "blue" and triches, "hair," hence, blue hair.
Physical Properties:
Cleavage:
[???] Good
Color:
sky blue, light blue, or dark blue.
Density:
2.7 - 2.74, Average = 2.72
Habits:
Druse - Crystal growth in a cavity which results in numerous crystal tipped surfaces., Acicular - Occurs as needle-like crystals., Spherical - Spherical, rounded aggregates.
Hardness:
2 - Gypsum
Luminescence:
None.
Luster:
Silky
Streak:
pale blue
More details...