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Biotite from
Spielman prospect (Spielman pegmatite), Devils Head Pegmatite Mining District, Douglas County, Colorado, USA


Locality type:Prospect
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 Spielman prospect (Spielman pegmatite), Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
Data Identifiers
Mindat Occurrence Record ID:355103
Long-form Identifier:1:3:355103:5
GUID (UUID V4):0
Nearest other occurrences of Biotite
0.0km (0.0 miles) ⓘLost Dutchman pegmatite, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
4.1km (2.6 miles) ⓘDenver Mine, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
5.3km (3.3 miles) ⓘFern Creek, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
5.4km (3.4 miles) ⓘRusty Pick Occurrence, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
7.3km (4.5 miles) ⓘLittle Anna, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
12.3km (7.6 miles) ⓘDevils Head Occurrence (C.M.S.), Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
13.7km (8.5 miles) ⓘSnowflake Feldspar Mine, Teller County, Colorado, USA
14.4km (9.0 miles) ⓘCramer Mine (Magnuson Quarry), Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
14.6km (9.1 miles) ⓘCramer No. 2 Quarry (Snowdrift Quarry), Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
15.8km (9.8 miles) ⓘThree Musketeers Mine, Devils Head Pegmatite Mining District, Douglas County, Colorado, USA
References
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
 
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