Plancheite

Plancheite


Composition: Cu8(Si4O11)2(OH)4.H2O
Crystal System : Orthorhombic
Colours: Pale-blue
Lustre : Satiny, earthy
Hardness (H) : 5.5
Specific Gravity (S.G) : 3.82
References: Keller (1977a)

Distribution

Rare. First (?) and second oxidation zones.

Occurrence

  • Supergene
  • 1st Oxidation Zone
  • 2nd Oxidation Zone

Paragenetic and General Notes

Plancheite occurs as whitish-blue, or bright-blue powdery crusts or coatings associated with dioptase (Bartelke, 1976). Less commonly, as radially-structured, spheroidal aggregates (to 1 or 2 mm).

Plancheite has been reported to form pseudomorphs after the following minerals:  azurite (rare), cuprite (rare).