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Illite from
Force Crag Mine, Coledale, Above Derwent, Allerdale, 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:367 Ma
Minimum recorded age:349 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1349 MaMississippian - K-Ar
2367 MaLate/Upper Devonian - K-Ar
3365 MaLate/Upper Devonian - 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
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Illite data
Locality Data:Click here to view Force Crag Mine, Coledale, Above Derwent, Allerdale, Cumbria, England, UK
Data Identifiers
Mindat Occurrence Record ID:16537
Long-form Identifier:1:3:16537:0
GUID (UUID V4):0
Nearest other occurrences of Illite
4.2km (2.6 miles) ⓘGoldscope Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
4.8km (3.0 miles) ⓘYewthwaite Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
4.8km (3.0 miles) ⓘThornthwaite Mine, Thornthwaite, Above Derwent, Allerdale, Cumbria, England, UK
5.3km (3.3 miles) ⓘCastle Nook Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
9.7km (6.0 miles) ⓘWad Mine, Seathwaite, Borrowdale, Allerdale, Cumbria, England, UK
11.0km (6.9 miles) ⓘBrundholme Mine (Glenderaterra Mine; Blencathra Mine), Glenderaterra Valley, Threlkeld, Eden, Cumbria, England, UK
13.3km (8.2 miles) ⓘThrelkeld Mine, Threlkeld, Threlkeld, Eden, Cumbria, England, UK
16.3km (10.1 miles) ⓘRoughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
16.3km (10.2 miles) ⓘRoughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
16.7km (10.4 miles) ⓘCarrock Mine, Mungrisdale, Eden, Cumbria, England, UK
References
 
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