Vote for your favorite mineral in #MinCup26! - Hafnon vs. Putnisite
It's a pair of tiny minerals of unusual chemistry as orange Hafnon battles with purple Putnisite.
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Biotite from
The Narrows, Big Thompson Canyon Area, Larimer County, Colorado, USA


Locality type:Canyon
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 The Narrows, Big Thompson Canyon Area, Larimer County, Colorado, USA
Data Identifiers
Mindat Occurrence Record ID:434542
Long-form Identifier:1:3:434542:8
GUID (UUID V4):0
Nearest other occurrences of Biotite
22.3km (13.8 miles) ⓘWisdom Ranch Prospect, Crystal Mountain Pegmatite Mining District (Storm Mountain Mining District), Larimer County, Colorado, USA
32.1km (20.0 miles) ⓘBig Narrows area, Larimer County, Colorado, USA
33.1km (20.6 miles) ⓘRusty Gold Mine (Copper Blush occurrence), Jamestown Mining District, Boulder County, Colorado, USA
39.5km (24.5 miles) ⓘBeryl No. 1 claim, Gold Hill Mining District, Boulder County, Colorado, USA
41.2km (25.6 miles) ⓘWilson beryl prospect, Gold Hill Mining District, Boulder County, Colorado, USA
42.5km (26.4 miles) ⓘSoda Springs Group, Mayesville Mining District, Larimer County, Colorado, USA
44.7km (27.7 miles) ⓘMayesville Mining District, Larimer County, Colorado, USA
45.8km (28.4 miles) ⓘEast Inlet area, Grand County, Colorado, USA
48.9km (30.4 miles) ⓘHome, Home Mining District, Larimer County, Colorado, USA
54.4km (33.8 miles) ⓘBennett Mine (Hell Hole claims), Wheeler Basin, Grand County, Colorado, USA
References
Eckel, Edwin Butt; Cobban, Robert R.; Mosburg, Shirley K.; Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing.
 
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