Crystal System: Trigonal
Status of Occurrence: Confirmed Occurrence - 1st UK recording
Chemical Composition: Light rare-earth aluminium phosphate hydroxide
Chemical Formula: (Ce,La)Al3(PO4)2(OH)6
Method(s) of Verification: Corris area - EMPA (A.T. Kearsley, Natural History Museum, unpublished data).
- Sedimentary: allogenic (detrital)
Introduction: florencite-(Ce) belongs to the phosphate subgroup of the alunite supergroup of minerals. It has a wide range of reported occurrences in the literature, these include, an accessory mineral in pegmatites and amphibolite grade metamorphic rocks and a minor phase within gold-sulphide and also copper deposits. However florencite is most commonly cited as a detrital mineral in various placer deposits (see Nriagu & Moore, 1984 for further details).
Occurrence in Wales: florencite was identified by energy dispersive electron microprobe analysis of Ordovician mudstones from the Corris district of Gwynedd. Qualitative analyses suggest that this is florencite-(Ce).
There are no key localities for this specimen.
- Nriahu, J.O. & Moore, P.B. (Eds), 1984. Phosphate Minerals. Springer-Verlag, 442pp.