You are here:  >   >   >   >   >   > 
Cymraeg

Adamite

Crystal System: Orthorhombic
Status of Occurrence: Discredited Occurrence
Distribution: None - Discredited
Chemical Composition: Zinc arsenate hydroxide
Chemical Formula: Zn2AsO4(OH)
Method(s) of Verification: XRD & EMPA at Manchester Museum has demonstrated that the species present at Dolyhir Quarry is actually zincolivenite.

Chemical Group:

Geological Context:

Introduction: adamite is a supergene mineral typically formed by the oxidation of base-metal sulphides and sulpharsenides. It is typically associated with other supergene arsenate minerals. Adamite forms a series with the copper arsenate olivenite, with zincolivenite chemically intermediate between the two.
Occurrence in Wales: adamite was reported by Bevins and Mason (1997) as part of a diverse arsenate-rich suite of secondary minerals extensively developed along the margins of a baryte-tennantite-galena-chalcopyrite vein temporarily exposed at Dolyhir Quarry, near Old Radnor in Powys. The secondary assemblage is dominated by copper minerals and the green colour of the adamite from Dolyhir led to many specimens being labelled as cuprian adamite. Further investigations have shown that the mineral present at Dolyhir is actually the recently described species, zincolivenite (T.F. Cotterell/D.I. Green, unpublished data).

Key Localities:

There are no key localities for this specimen.

References:

  1. Bevins, R.E. & Mason, J.S., 1997. Welsh metallophyte and metallogenic evaluation project: Results of a minesite survey of Dyfed and Powys. CCW Contract Science Report No. 156. National Museums & Galleries of Wales.