Crystal System: Orthorhombic
Status of Occurrence: Unconfirmed Occurrence
Distribution: Rare
Chemical Composition: Copper calcium arsenate hydroxide
Chemical Formula: CaCuAsO4OH
Method(s) of Verification: Dolyhir Quarry - electron microprobe (to be confirmed).

Chemical Group:

  • Arsenates

Geological Context:

  • Supergene: in situ natural oxidation & weathering deposits
Introduction: conichalcite is a supergene mineral occurring, with other supergene arsenates, in the oxidized zones of copper- and arsenic-bearing hydrothermal ore deposits.
Occurrence in Wales: conichalcite has been tentatively identified on a specimen collected at Dolyhir Quarry, by electron microprobe qualitative analysis (which showed Ca, Cu and As to be the elements present). X-ray diffraction is required for fully conclusive results as there are a number of supergene minerals containing these elements.

Key Localities:

  • Dolyhir Quarry, Old Radnor, Powys: conichalcite occurs as green crusts with azurite and malachite (D.I. Green, unpublished data). The colour and composition are compatible with conichalcite, but further material is required in order to perform an XRD analysis.


There are no references for this specimen.