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Illite from
Yewthwaite Mine, Newlands Valley, 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:362 Ma
Minimum recorded age:345 Ma
Sample ages:
Recorded ageGeologic TimeSampleDating method
1345 MaMississippian - K-Ar
2362 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
Confirmation
Validity:Believed Valid
Data
Mineral Data:Click here to view Illite data
Locality Data:Click here to view Yewthwaite Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
Data Identifiers
Mindat Occurrence Record ID:16543
Long-form Identifier:1:3:16543:1
GUID (UUID V4):0
Nearest other occurrences of Illite
1.6km (1.0 miles) ⓘGoldscope Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
2.7km (1.7 miles) ⓘCastle Nook Mine, Newlands Valley, Above Derwent, Allerdale, Cumbria, England, UK
4.8km (3.0 miles) ⓘForce Crag Mine, Coledale, Above Derwent, Allerdale, Cumbria, England, UK
6.8km (4.2 miles) ⓘThornthwaite Mine, Thornthwaite, Above Derwent, Allerdale, Cumbria, England, UK
6.9km (4.3 miles) ⓘWad Mine, Seathwaite, Borrowdale, Allerdale, Cumbria, England, UK
9.6km (5.9 miles) ⓘBrundholme Mine (Glenderaterra Mine; Blencathra Mine), Glenderaterra Valley, Threlkeld, Eden, Cumbria, England, UK
10.8km (6.7 miles) ⓘThrelkeld Mine, Threlkeld, Threlkeld, Eden, Cumbria, England, UK
12.3km (7.6 miles) ⓘGreenside Mine, Patterdale, Eden, Cumbria, England, UK
16.0km (9.9 miles) ⓘCarrock Mine, Mungrisdale, Eden, Cumbria, England, UK
16.3km (10.1 miles) ⓘRoughton Gill Mine, Roughton Gill, Caldbeck, Allerdale, Cumbria, England, UK
References
Day, Harry (1999) BMS Database, British Micromount Society.
 
and/or  
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