Köttigite

Köttigite


Composition: Zn3(AsO4)2.8H2O
Crystal System : Monoclinic
Colours: White, brown, red, blue
Lustre : Silky
Hardness (H) : 2.5
Specific Gravity (S.G) : 3.3
References: Gebhard (1999)

Distribution

Very rare. Second (?) and third oxidation zones.

Occurrence

  • Supergene
  • 2nd Oxidation Zone
  • 3rd Oxidation Zone

Notable Finds

The so-called "Zinc Pocket" on 44 Level, in the third oxidation zone.

Paragenetic and General Notes

Köttigite was first observed at Tsumeb by Bartelke (1976) who described radiating clusters of needle-like crystals (to 2 mm) associated with "dark-green adamite" (presumably cuprian adamite or zincolivenite).  This material was probably from the second oxidation zone.

In the third oxidation zone, köttigite occurred in the so-called "Zinc Pocket", on 44 Level, from which Gebhard (1999) described blue balls of köttigite associated with leiteite and white adamite.