Crystal System: Monoclinic
Status of Occurrence: Confirmed Occurrence
Distribution: Rare
Chemical Composition: Lead zinc silicate sulphate
Chemical Formula: Pb4Zn2SO4SiO4Si2O7
Method(s) of Verification: Penrhiw Mine - EMPA shows Pb, Zn, Si and S in similar ratios to queitite from Red Gill Mine, Caldbeck Fells (Mason & Green, 1995).

Geological Context:

  • Supergene: post-mining oxidation & weathering deposits
Introduction: queitite is an extremely rare secondary mineral typically developed in the oxidized zone of lead-zinc bearing ore bodies and through post-mining alteration of lead-zinc ore.
Occurrence in Wales: a single specimen displaying microscopic crystal sprays was collected from weathered veinstone in a small section of dumps at Penrhiw Mine in the Central Wales Orefield.

Key Localities:

  • Penrhiw Mine, Ystumtuen, Ceredigion: found on a single specimen as aggregates of minute lath like crystals to about 50 μm in length (Mason & Green, 1995).


  1. Mason, J.S. & Green, D.I., 1995. Supergene minerals including exceptional ramsbeckite from Penrhiw Mine, Ystumtuen, Dyfed. UK Journal of Mines & Minerals, 15, 21-27.