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The Broad Vein is one of the two major slate veins in Mid Wales that were commercially quarried. Broad Vein rock is generally dense, with few natural joints, so most of the commercial use was for slab and products such as mantlepieces, cisterns and (later) electrical switchboards. Production of
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The formation is exposed in a number of locations in Mid Wales where glacial valleys cut across it. It is especially visible in the quarries along its length.
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in several locations along its length. The formation is between 400 metres (1,300 ft) and 560 metres (1,840 ft) thick and runs from
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in places. It varies in colour from a pale to a medium blue. This formation has been commercially quarried as
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which worked from the 14th. century until 2002. Also worked the Narrow Vein. Connected to the
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The Slate
Regions of North and Mid Wales and Their Railways
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roofing slates was relatively rare in Broad Vein quarries.
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The Broad Vein was quarried in the following locations:
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269:was also worked, connected to the
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382:BGS on-line lexicon of rock units
353:BGS on-line lexicon of rock units
378:"Broad Vein Mudstone Formation"
349:"Broad Vein Mudstone Formation"
76:Narrow Vein Mudstone Formation
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182:Broad Vein Mudstone Formation
48:which quarried the Broad Vein
21:Broad Vein Mudstone Formation
406:Richards, Alun John (1999).
188:, historically known as the
438:Ordovician System of Europe
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386:British Geological Survey
357:British Geological Survey
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448:Rock formations of Wales
453:Slate industry in Wales
443:Upper Ordovician Series
410:. Gwasg Carreg Gwalch.
184:(commonly known as the
280:Upper Corris Tramway
276:Abercwmeiddaw quarry
250:Commercial quarrying
42:Abercwmeiddaw quarry
327:, connected to the
312:Maes-y-gamfa quarry
294:Aberllefenni Quarry
141: /
27:Stratigraphic range
316:Hendre-Ddu Tramway
201:lithostratigraphic
145:52.6632°N 3.8453°W
86:Nod Glas Formation
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192:and in Welsh as
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150:52.6632; -3.8453
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67:Abercorris Group
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29:: Hirnantian Age
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329:Mawddwy Railway
307:Ratgoed Tramway
285:Cambergi quarry
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206:(a sequence of
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321:Minllyn quarry
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391:11 September
389:. Retrieved
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360:. Retrieved
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232:Cardigan Bay
218:, intensely
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46:Corris Uchaf
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267:Narrow Vein
263:Bryn Eglwys
220:bioturbated
208:rock strata
194:Y Faen Goch
148: /
123:Coordinates
432:Categories
335:References
289:Cwm Hengae
265:where the
198:Ordovician
186:Broad Vein
133:52°39′48″N
362:6 January
212:Mid Wales
165:Mid Wales
136:3°50′43″W
92:Lithology
72:Underlies
242:Outcrops
216:mudstone
196:) is an
190:Red Vein
117:Location
101:Mudstone
82:Overlies
323:, near
171:Country
97:Primary
64:Unit of
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161:Region
236:Tywyn
224:slate
210:) in
204:group
174:Wales
111:Slate
107:Other
58:Group
412:ISBN
393:2019
364:2020
180:The
54:Type
40:The
287:in
234:at
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
