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Illite from
Thornthwaite Mine, Thornthwaite, 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:365 Ma
Minimum recorded age:311 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1311 MaPennsylvanian - K-Ar
2362 MaLate/Upper Devonian - K-Ar
3339 MaMississippian - K-Ar
4314 MaPennsylvanian - K-Ar
5365 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
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
5 -
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 Thornthwaite Mine, Thornthwaite, Above Derwent, Allerdale, Cumbria, England, UK
Data Identifiers
Mindat Occurrence Record ID:16541
Long-form Identifier:1:3:16541:3
GUID (UUID V4):0
Nearest other occurrences of Illite
4.8km (3.0 miles) ⓘForce Crag Mine, Coledale, Above Derwent, Allerdale, Cumbria, England, UK
6.8km (4.2 miles) ⓘYewthwaite Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
7.3km (4.5 miles) ⓘBrundholme Mine (Glenderaterra Mine; Blencathra Mine), Glenderaterra Valley, Threlkeld, Eden, Cumbria, England, UK
7.3km (4.5 miles) ⓘGoldscope Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
8.8km (5.5 miles) ⓘCastle Nook Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
10.1km (6.3 miles) ⓘThrelkeld Mine, Threlkeld, Threlkeld, Eden, Cumbria, England, UK
11.6km (7.2 miles) ⓘRoughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
11.6km (7.2 miles) ⓘRoughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
12.2km (7.6 miles) ⓘCarrock Mine, Mungrisdale, Eden, Cumbria, England, UK
13.4km (8.3 miles) ⓘWad Mine, Seathwaite, Borrowdale, Allerdale, Cumbria, England, UK
References
Day, Harry (1999) BMS Database, British Micromount Society.
 
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