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Birnessite from
Greystone Quarry, Lezant, Cornwall, England, UK


Locality type:Quarry
Classification
Species:Birnessite
Formula:(Na,Ca)0.5(Mn4+,Mn3+)2O4 · 1.5H2O
Comments:Although a near Birnessite mineral was recorded by Golley and Williams 1995, recent analysis of similar material although showing manganese, calcium and lead to be present, gave an XRD pattern that could not be matched with any known species

Confirmation
Validity:Unconfirmed/Questioned
Data
Mineral Data:Click here to view Birnessite data
Locality Data:Click here to view Greystone Quarry, Lezant, Cornwall, England, UK
Data Identifiers
Mindat Occurrence Record ID:2001
Long-form Identifier:1:3:2001:5
GUID (UUID V4):0
Nearest other occurrences of Birnessite
12.6km (7.8 miles) ⓘTreburland Manganese Mine (Treburland manganese deposits), Altarnun, Cornwall, England, UK
93.9km (58.3 miles) ⓘPenberthy Croft Mine, St Hilary, Cornwall, England, UK
References
Elton, N., Green, D., Hooper, J., Weiss, S. (2004) Famous British Mineral Localities: Greystone Quarry, Lezant, Cornwall. UK Journal of Mines and Minerals 24, Rockbottom Publications. 9-28
 
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