Yvonite

General Information:
 Chemical Formula:
Cu(AsO3OH)·2(H2O)
 Composition:
(Molecular Weight = 239.50 gm)
Copper 26.53 % Cu
Arsenic 31.28 % As
Hydrogen 2.10 % H 
Oxygen 40.08 % O 
 Empirical Formula:
Cu(AsO3OH)·2(H2O)
 Environment:
Gold-bearing sulfo-arsenic ore.
 IMA Status:
Approved IMA (Dana # Added)
 Locality:
Salsigne mine near Carcassone, Aude, France.
 Name Origin:
Named in honor of Klaus Yvon, professor of crystallography at the University of Geneva, Switzerland.
Physical Properties:
 Cleavage:
[100] Perfect, [010] Poor
 Color:
turquoise blue.
 Density:
3.2
 Diaphaniety:
Transparent
 Habits:
Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite), Spherical - Spherical, rounded aggregates.,
 Hardness:
3.5-4 - Copper Penny-Flourite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous (Glassy)
 Streak:
blue
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