Mineral Database (Saesneg yn unig)

Mineral Database (Saesneg yn unig)
Mineralogy of Wales

Plumbojarosite

Crystal System: Trigonal
Formula: PbFe63+(SO4)4(OH)12
Status of Occurrence: Unconfirmed Occurrence
Distribution: Rare
Chemical Composition: Lead iron sulphate hydroxide
Method(s) of Verification: Ystrad Einion Mine - not fully verified. XRD of a beaverite specimen at the Natural History Museum, London indicated a little plumbojarosite may be present (Wirth, 1993).
Geological Context:
  • Supergene : post-mining oxidation & weathering deposits
Introduction: a secondary sulphate belonging to the alunite group of minerals. Plumbojarosite is common in the oxidized zone of lead mines in arid regions.
Occurrence in Wales: tentatively identified from Ystrad Einion Mine in the Central Wales Orefield on the basis of contamination in beaverite analysed at the Natural History Museum, London (Wirth, 1993). However, Mason & Rust (1997) give no mention of plumbojarosite in their detailed review of the mineralogy of Ystrad Einion Mine thus, suggesting that the original record has been discredited.
Key Localities:
  • Ystrad Einion Mine, Furnace, Ceredigion: noted during XRD analysis as a possible associate with beaverite (Wirth, 1993). No further details are recorded, other than that a piece of this material is in the British Micromount Society reference collection (No. 1326).
References:
  • Mason, J.S. & Rust, S.A., 1997 The Mineralogy of Ystrad Einion Mine, Dyfed, Wales.  U.K. Journal of Mines and Minerals, 18, 33-36.
  • Wirth, M., 1993 Recent additions (Nos. 1301-1400) to the BMS collection.  British Micromount Society Newsletter, No. 35, 15-16.