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Biotite from
Cajalco Mine (Cajalco Tin Mine; Cajalco Dumortierite occurrence), El Cerrito, Riverside County, California, USA


Locality type:Mine
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Cajalco Mine (Cajalco Tin Mine; Cajalco Dumortierite occurrence), El Cerrito, Riverside County, California, USA
Data Identifiers
Mindat Occurrence Record ID:633683
Long-form Identifier:1:3:633683:7
GUID (UUID V4):0
Nearest other occurrences of Biotite
9.1km (5.6 miles) ⓘUnnamed Vermiculite occurrence [1], La Sierra, Riverside, Riverside County, California, USA
17.6km (11.0 miles) ⓘOld City Quarry (City Quarry; North Hill Quarry; Quarry Hill; Fairmount), Riverside, Riverside County, California, USA
19.3km (12.0 miles) ⓘJensen Quarry, Jurupa Mountains, Jurupa Valley, Riverside County, California, USA
20.3km (12.6 miles) ⓘCommercial Quarry, Sky Blue Hill, Crestmore quarries, Crestmore, Jurupa Valley, Riverside County, California, USA
21.9km (13.6 miles) ⓘBox Springs Mountains, Riverside County, California, USA
32.1km (19.9 miles) ⓘSouthern Pacific Silica Quarry (Southern Pacific deposit; Nuevo Mine; Southern Pacific Quarry; S.P. Silica Quarry; S.P. Mine; Nuevo Quarry), Nuevo, Lakeview Mountains, Riverside County, California, USA
38.7km (24.1 miles) ⓘUnnamed abandoned quarry (Unnamed small gravel quarry), Claremont, Los Angeles County, California, USA
52.0km (32.3 miles) ⓘHazen Corundum prospect (Unnamed Corundum prospect), Soboba Hot Springs (Ritchey Hot Springs; White Sulphur Spring), San Jacinto Mountains, Riverside County, California, USA
52.1km (32.4 miles) ⓘUnnamed Corundum occurrences [2], Soboba Hot Springs (Ritchey Hot Springs; White Sulphur Spring), San Jacinto Mountains, Riverside County, California, USA
57.9km (36.0 miles) ⓘSt. Patrick's group (St. Patrick claim; Alger Creek claims), Forest Falls (Fallsvale; Fallsville; Forest Home), San Bernardino County, California, USA
References
MacMurphy, F. (1930) Dumortierite in Riverside County, California. American Mineralogist, 15 (2) 79-80
 
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