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Illite from
Brundholme Mine (Glenderaterra Mine; Blencathra Mine), Glenderaterra Valley, Threlkeld, Eden, Cumbria, England, UK


Locality type:Mine
Classification
Species:Muscovite var: Illite
Formula:K0.65Al2.0[Al0.65Si3.35O10](OH)2
Age information
Maximum recorded age:340 Ma
Minimum recorded age:272 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1272 MaGuadalupian - K-Ar
2284 MaCisuralian - K-Ar
3332 MaMississippian - K-Ar
4340 MaMississippian - K-Ar
Sample references:
1 -
Ineson, P. R., Mitchell, J. G. (1974) K-Ar isotopic age determinations from some Lake District mineral localities. Geological Magazine, 111 (6). 521-537 doi:10.1017/s0016756800041571
2 -
Ineson, P. R., Mitchell, J. G. (1974) K-Ar isotopic age determinations from some Lake District mineral localities. Geological Magazine, 111 (6). 521-537 doi:10.1017/s0016756800041571
3 -
Ineson, P. R., Mitchell, J. G. (1974) K-Ar isotopic age determinations from some Lake District mineral localities. Geological Magazine, 111 (6). 521-537 doi:10.1017/s0016756800041571
4 -
Ineson, P. R., Mitchell, J. G. (1974) K-Ar isotopic age determinations from some Lake District mineral localities. Geological Magazine, 111 (6). 521-537 doi:10.1017/s0016756800041571
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Illite data
Locality Data:Click here to view Brundholme Mine (Glenderaterra Mine; Blencathra Mine), Glenderaterra Valley, Threlkeld, Eden, Cumbria, England, UK
Data Identifiers
Mindat Occurrence Record ID:16534
Long-form Identifier:1:3:16534:3
GUID (UUID V4):0
Nearest other occurrences of Illite
3.1km (1.9 miles) ⓘThrelkeld Mine, Threlkeld, Threlkeld, Eden, Cumbria, England, UK
6.5km (4.0 miles) ⓘCarrock Mine, Mungrisdale, Eden, Cumbria, England, UK
7.3km (4.5 miles) ⓘThornthwaite Mine, Thornthwaite, Above Derwent, Allerdale, Cumbria, England, UK
7.3km (4.5 miles) ⓘRoughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
7.3km (4.5 miles) ⓘRoughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
8.8km (5.5 miles) ⓘDriggith Mine, Caldbeck, Allerdale, Cumbria, England, UK
9.4km (5.8 miles) ⓘOld Sandbed Mine, Caldbeck, Allerdale, Cumbria, England, UK
9.6km (5.9 miles) ⓘYewthwaite Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
9.6km (6.0 miles) ⓘOld Potts Gill Mine, Potts Gill, Caldbeck, Allerdale, Cumbria, England, UK
11.0km (6.8 miles) ⓘGoldscope Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
References
Day, Harry (1999) BMS Database, British Micromount Society.
 
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