General Information:
Chemical Formula:
Cu8Si8O22(OH)4·(H2O)
Composition:
(Molecular Weight = 1,171.08 gm)
Copper 43.41 % Cu
Silicon 19.19 % Si
Hydrogen 0.52 % H
Oxygen 36.89 % O
Empirical Formula:
Cu8Si8O22(OH)4·(H2O)
Environment:
Secondary mineral in the oxidized zones of copper deposits.
IMA Status:
Approved IMA 1968
Locality:
Tantara and Kambowe, Zaire.
Name Origin:
Named after J. Planche who brought it from Africa.
Physical Properties:
Color:
blue or greenish blue.
Density:
3.6 - 3.8, Average = 3.7
Diaphaniety:
Translucent
Habits:
Fibrous - Crystals made up of fibers., Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Acicular - Occurs as needle-like crystals.
Hardness:
5.5 - Knife Blade
Luminescence:
None.
Luster:
Adamantine - Silky
Streak:
light blue
More details...