CHENEVIXITE
Class : Phosphates, arsenates, vanadates
Subclass : Hydrated arsenates
Crystal system : Monoclinic
Chemistry : Cu2Fe2(AsO4)2(OH)4 H2O
Rarity : Quite common
Chenevixite is a hydrated arsenate of iron and copper quite widely distributed in the oxidation zone of certain polymetallic hydrothermal copper deposits, but always in very small quantities. It accompanies other secondary copper minerals (arsenates and carbonates in particular). Its name was given to it in honor of the French chemist Richard Chenevix who carried out the first analysis of this mineral. It occurs in small tabular crystals (less than 0.5 mm), usually gathered in earthy microcrystalline encrustations or in spheroidal aggregates, sometimes acicular, yellow-green to dark green in color.
Main photo : Chenevixite from Christiana Mine, Lavrion, Greece © Fritz Schreiber
Chenevixite in the World
Twinning
No twins known for this mineral species. Can replace bariopharmacosiderite (pseudomorph) at the Clara Mine (Germany) in particular.
Fakes and treatments
No fake identified for this mineral species.
Hardness : 3.5 to 4.5
Density : 4.38
Fracture : Sub-conchoidal
Streak : Green-yellow
TP : Translucent to transparent
RI : 1.920 to 2.040
Birefringence : 0.120
Optical character : Biaxial +
Pleochroism : Low
Fluorescence : None
Solubility : Acids
Magnetism : None
Radioactivity : None