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Biotite from
Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA


09324320017272025861171.jpg
Biotite

Granite Mountain Quarry No. 1, Granite Mountain Area, Little Rock, Pulaski County, Arkansas, USA
07435660017272033691244.jpg
Biotite, etc.

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
00860820017272026041868.jpg
Biotite

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
00771550017272025751547.jpg
Biotite

Granite Mountain Quarry No. 1, Granite Mountain Area, Little Rock, Pulaski County, Arkansas, USA
01263900017272011522537.jpg
Biotite, etc.

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
04976380017272011559879.jpg
Biotite

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
09324320017272025861171.jpg
Biotite

Granite Mountain Quarry No. 1, Granite Mountain Area, Little Rock, Pulaski County, Arkansas, USA
01263900017272011522537.jpg
Biotite, etc.

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
04976380017272011559879.jpg
Biotite

Big Rock Quarry, Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
Locality type:Area
Classification
Species:'Biotite' (not an IMA approved species)
Formula:K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Age information
Maximum recorded age:94 ± 5 Ma
Minimum recorded age:89 ± 4 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
189 ± 4 MaLate/Upper Cretaceous - K-Ar
294 ± 5 MaLate/Upper Cretaceous - K-Ar
389 ± 3 MaLate/Upper Cretaceous - Rb-Sr
Sample references:
1 -
Zartman, R.E., Brock, M.R., Heyl, A.V., and Thomas, H.H. (1967) K-Ar and Rb-Sr ages of some alkalic intrusive rocks from central and eastern United States. American Journal of Science, vol. 265, pp. 848-870.
2 -
Zartman, R.E., Brock, M.R., Heyl, A.V., and Thomas, H.H. (1967) K-Ar and Rb-Sr ages of some alkalic intrusive rocks from central and eastern United States. American Journal of Science, vol. 265, pp. 848-870.
3 -
Zartman, R.E., Brock, M.R., Heyl, A.V., and Thomas, H.H. (1967) K-Ar and Rb-Sr ages of some alkalic intrusive rocks from central and eastern United States. American Journal of Science, vol. 265, pp. 848-870.
Confirmation
Validity:Believed Valid
Associated Minerals Based on Photo Data:
Titanite2
Stilbite Subgroup1
Orthoclase1
Chlorite Group1
Data
Mineral Data:Click here to view Biotite data
Locality Data:Click here to view Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
Data Identifiers
Mindat Occurrence Record ID:87657
Long-form Identifier:1:3:87657:3
GUID (UUID V4):0
Localities for Biotite in this Region
Big Rock Quarry (3M Quarry; Arch Street Pike Quarry), Granite Mountain area, Little Rock, Pulaski County, Arkansas, USA
References
Smith, Arthur E. Jr. (1988) Arkansas Mineral Locality Index. Rocks & Minerals, 63 (2) 104-125 doi:10.1080/00357529.1988.11761826
Barwood, Henry L. (1989) Mineralogy of the Granite Mountain Syenite. Rocks & Minerals, 64 (4) 314-322 doi:10.1080/00357529.1989.11761773
 
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