Mineralization of England and Wales
R.E. Bevins Department of Geology, National Museum Wales, Cardiff
B. Young Department of Earth Sciences, University of Durham (formerly British Geological Survey)
J.S. Mason Department of Geology, National Museum Wales, Cardiff
D.A.C. Manning Institute for Research on Environment and Sustainability, Newcastle University
R.F. Symes Geologist/Mineralogist, Sidmouth
with contributions from R.A.D. Pattrick (University of Manchester) A. Clark (Mineral Solutions Ltd) A. Thurston (Mineral Solutions Ltd) J. Vetterlein (Mineral Solutions Ltd) J. Aumonier (The Mineral Industry Research Organisation (MIRO)) M.L. White (Mineral Solutions Ltd) G. Warrington (formerly British Geological Survey)
Based in part on primary work by Dr L. Haynes GCR Editors: L.P. Thomas and E.L. Durham
Published by the Joint Nature Conservation Committee, Monkstone House, City Road, Peterborough, PE1 1JY, UK
First edition 2010
2010 Joint Nature Conservation Committee
Typeset in 10/12pt Garamond ITC by JNCC
Printed in Great Britain by Hobbs The Printers, Totton.
ISBN 978 1 86107 566 6
Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the UK Copyright Designs and Patents Act, 1988, this publication may not be reproduced, stored, or transmitted, in any form or by any means, without the prior permission in writing of the publishers, or in the case of reprographic reproduction only in accordance with the terms of the licences issued by the Copyright Licensing Agency in the UK, or in accordance with the terms and licences issued by the appropriate Reproduction Rights Organization outside the UK. Enquiries concerning reproduction outside the terms stated here should be sent to the GCR Team, JNCC.
The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made.
British Geological Survey Copyright protected materials
- The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council (NERC). No part of these materials (geological maps, charts, plans, diagrams, graphs, cross-sections, figures, sketch maps, tables, photographs) may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the written permission of the copyright holder, in advance.
- To ensure that copyright infringements do not arise, permission has to be obtained from the copyright owner. In the case of BGS maps this includes both BGS and the Ordnance Survey. Most BGS geological maps make use of Ordnance Survey topography (Crown Copyright), and this is acknowledged on BGS maps. Reproduction of Ordnance Survey materials may be independently permitted by the licences issued by Ordnance Survey to many users. Users who do not have an Ordnance Survey licence to reproduce the topography must make their own arrangments with the Ordnance Survey, Copyright Branch, Romsey Road, Southampton SO9 4DH (Tel. 01703 792913).
- Permission to reproduce BGS materials must be sought in writing from the Intellectual Property Rights Manager, British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (Tel. 0115 936 3100).
A catalogue record for this book is available from the British Library.
Recommended example citations
Bevins, R.E., Young, B., Mason, J.S., Manning, D.A.C. and Symes, R.F. (2010) Mineralization of England and Wales, Geological Conservation Review Series, No. 36, Joint Nature Conservation Committee, Peterborough, 598 pp.
Young, B. (2010) Stonecroft Mine. In Mineralization of England and Wales (R.E. Bevins, B. Young, J.S. Mason, D.A.C. Manning and R.F. Symes), Geological Conservation Review Series, No. 36, Joint Nature Conservation Committee, Peterborough, pp. 112–14.
Contents
Acknowledgements
Access to the countryside
Conserving our mineral heritage — JNCC policy statement
Preface N.V Ellis
1 Mineralization in England and Wales: an introduction R.E. Bevins
Background
GCR site selection
Mineralization history of England and Wales
2 The Lake District B. Young
Introduction
Seathwaite Graphite Mine, Cumbria
Water Crag, Cumbria
Coniston Copper Mines, Cumbria
Birk Fell Hawse Mine, Cumbria
Dale Head North and South Veins, Cumbria
Wet Swine Gill, Cumbria
Carrock Mine–Brandy Gill, Cumbria
Buckbarrow Beck, Cumbria
Long Comb, Cumbria
Red Gill Mine, Cumbria
Roughtongill Mine, Cumbria
Dry Gill Mine, Cumbria
Eagle Crag, Cumbria
Florence Mine, Cumbria
Nab Gill Mine, Cumbria
Seathwaite Copper Mines, Cumbria
Force Crag Mine, Cumbria
3 The Northern Pennines B. Young
Introduction
West Rigg Opencut, Durham
Killhope Head, Durham
Smallcleugh Mine, Cumbria
Tynebottom Mine, Cumbria
Sir John's Mine, Cumbria
Scordale Mines, Cumbria
Lady's Rake Mine, Durham
Willyhole Mine, Durham
Pike Law Mines, Durham
Blagill Mine, Cumbria
Settlingstones Mine, Northumberland
Stonecroft Mine, Northumberland
Fallowfield Mine, Northumberland
Closehouse Mine, Durham
Foster's Hush, Durham
Black Scar, Middleton Tyas, North Yorkshire
Cumpston Hill North and South Veins, Cumbria
Greenhow (Duck Street) Quarry, North Yorkshire
Pikedaw Calamine and Copper Mines, North Yorkshire
Gunnerside Gill, Swaledale, North Yorkshire
4 South Pennine Orefield: Cheshire, Leicestershire and Shropshire D.A.C. Manning, with contributions from R.A.D. Pattrick, A. Clark, A. Thurston, J. Vetterlein, J. Aumonier and M.L. White
Introduction
Castle Hill Quarry (Mountsorrel Granite Quarry), Leicestershire
Croft Quarry, Leicestershire
Newhurst Quarry, Leicestershire
Warren Quarry, Leicestershire
Gipsy (Gypsy) Lane Brick Pit, Leicestershire
Calton Hill, Derbyshire
Masson Hill Mines, Derbyshire
Dirtlow Rake and Pindale, Derbyshire
Bage Mine, Derbyshire
Fall Hill Quarry, Derbyshire
Treak Cliff, Derbyshire
Windy Knoll, Derbyshire
Portway Gravel Pits, Derbyshire
Kirkham's Silica Sandpits, Derbyshire
Ecton Copper Mines, Derbyshire
Alderley Edge District, Cheshire G. Warrington
Snailbeach Mine, Shropshire
Huglith Mine, Shropshire
5 Wales R.E. Bevins and J.S. Mason
Introduction
Lower Palaeozoic iron and manganese exhalative mineralization in North Wales
Llyn Du Bach Complex
Benallt and Nant Mines
Tyllau Mwn
Coed y Brenin porphyry copper system
Bryn-Coch and Capel Hermon
Glasdir Mine
Mod Hafod-Owen
Turf Copper Mine
Dolgellau Gold-belt
Foel-Ispri Mine
Cefn-Coch Mine
Friog Undercliff
Mineralization associated with Caradoc igneous activity in North Wales
Lliwedd Mine
Llanberis Mine
Cwm Tregalan–Shadow Gully
Llyn Cwellyn Mine
Bwlch Mine, Deganwy
Parys Mountain
Cae Coch Mine
Ffestiniog Granite Quarry
Afon Stwlan
Alpine-type veins cutting Caradoc and older sedimentary and igneous rocks
Manod Quarry
Coed Llyn y Garnedd
Penrhyn Quarry
Stratabound gold-arsenic mineralization associated with Lower Palaeozoic pyritic mudstones
Dolaucothi Mine
Quartz-sulphide vein mineralization of Devonian and Variscan age in Central Wales
Cwmystwyth Mine
Brynyrafr Mine
Darren Mine
Erglodd Mine
Eaglebrook (Nantycagl) Mine
Ceulan Mine Opencast
Nantiago Mine
Nantymwyn Mine
Copper-lead-arsenic-barium vein mineralization in the Welsh
Borderland
Dolyhir Quarry
Mississippi Valley-type lead-zinc-fluorite and copper-dolomite associations in north-east Wales
Halkyn Mountain
Pool Park and South Mincra Mines
Pennant Mine
Great Orme Copper Mines
Upper Palaeozoic millerite-bearing ironstones of the South Wales Coalfield
Mesozoic iron-manganese and lead-zinc-copper-barium mineralization in South Wales
Mwyndy Mine
Ton Mawr Quarry
Ogmore Coast
Machen Quarry
Secondary Mineralization
Llechweddhelyg Mine
Frongoch Mine
Mynydd Nodol Mine
6 The Mendip Hills R.F. Symes
Introduction
Banwell Caves, Avon
Banwell Ochre Caves, Avon
Ben Knowle, Somerset
Charterhouse Lead Orefield, Somerset
Clevedon Shore, Avon
Wurt Pit, Somerset
Compton Martin Ochre Mine, Somerset
Hartcliff Rocks Quarry, Avon
7 South-west England R. F. Symes
Introduction
Meldon Aplite Quarries, Devon
Priest's Cove, Cape Cornwall, Cornwall
Trevalour Downs Pegmatite, Cornwall
Tremearne Par, Cornwall
Red-a-Ven Mine, Meldon, Devon
Haytor Iron Mine, Devon
Botallack Mine and Wheal Owles, Cornwall
Wheal Coates, Cornwall
Lidcott Mine, Cornwall
Wheal Emily, Devon
Cligga Head, Cornwall
Cameron Quarry, Cornwall
St Michael's Mount, Cornwall
Mulberry Down Opencast, Cornwall
Great Wheal Fortune, Cornwall
Nanjizal Cove (Mill Cove), Cornwall
Devon Great Consols, Devon
Devon United Mine, Devon
Trevaunance Cove, St Agnes, Cornwall
Perran Beach to Holywell Bay, Cornwall
Lockridge Mine, Devon
South Terras Mine, Cornwall
Wheal Penrose, Porthleven, Cornwall
Wheal Alfred, Cornwall
Penberthy Croft Mine, Cornwall
Hope's Nose, Devon
High Down Quarry, Devon
Hingston Down Quarry and Hingston Down Consols, Cornwall
Penlee Quarry, Newlyn, Cornwall
Gravel Hill Mine, Cornwall
Dean Quarry, Lizard, Cornwall
References
Mineral index
General index
Acknowledgements
Work on selecting sites for the GCR for what was to become the Mineralization of England and Wales GCR volume (and its companion volume on the Mineralogy of Scotland) began over 30 years ago, for the Nature Conservancy Council (NCC). The initial GCR site selection was co-ordinated largely by Dr L. Haynes for the NCC, with significant involvement from T.D. Ford, J. Horak, R.J. King, W.I. Stanton, R.F. Symes and B. Young. Dr Haynes also embarked on a comprehensive site documentation and text preparation programme for the metallogenetic sites from the various regionally based GCR site selection categories (called 'Blocks' they covered the Lake District; the Mendips; the Peak District/Leicestershire/Cheshire and Shropshire (Southern Pennines); the Northern Pennines; South-West England; Scotland; and Wales). Dr Haynes produced a text prepared for publication under the guidance of the then GCR Editor-in-Chief, W.A. Wimbledon. The planned 'Metallogenesis' tide was in an advanced state when JNCC came into existence in 1990. A little while after the creation of JNCC and the country conservation agencies from what was formerly the NCC it was decided to publish accounts of the mineralization/mineralogy sites on a regional basis for the GCR Series of books. In part, this reflected the original site selection scheme and would help the newly formed country conservation agencies to justify the conservation case for the networks of sites in their care. Work began afresh on the present volume text in the late 1990s. However the initial documents were invaluable in the preparation of the new text, and great thanks are duly afforded to Dr Haynes.
The present volume is the combined work of the authors and contributors listed on page v. The Introduction (Chapter 1) was compiled and largely written by R.E. Bevins, but based in part on previous work by L. Haynes and B. Young. R.E. Bevins also compiled and wrote Chapter 5 (Wales) along with J.S. Mason, and R.E. Bevins oversaw the overall compilation and editing of the volume. Chapters 2 and 3 (The Lake District and The Pennines) were provided by B. Young; Chapter 4 (The Southern Pennines) by D.A.C. Manning (with contributions from R.A.D. Pattrick, A. Clark, A. Thurston, J. Vetterlein, J. Aumonier, M.L. White and G. Warrington); and Chapters 6 and 7 by R.F. Symes. The GCR editors, E.L. Durham and L.P. Thomas, provided feedback and guidance during the preparatory stages of the project. The project was managed by N.V. Ellis, GCR Publications Manager, JNCC and seen through to production by JNCC's editorial team, in particular E.L. Durham.
Diagrams were expertly drafted by S.C. White and C.F. Pamplin (JS Publications, Newmarket), and the index was prepared by Jane Angus. Photographs from the BGS collection are reproduced by kind permission of the Director, BGS, NERC, all rights reserved. Other suppliers of photographs and diagrammatic material are acknowledged in the figure captions.
On behalf of all of the authors and contributors, we would like to record our thanks to the owners and managers of land and quarries who have allowed access to the sites, either during previous work or specifically for this GCR volume.
Access to the countryside
This volume is not intended for use as a field guide. The description or mention of any site should not be taken as an indication that access to a site is open. Most sites described are in private ownership, and their inclusion herein is solely for the purpose of justifying their conservation. Their description or appearance on a map in this work should not be construed as an invitation to visit. Prior consent for visits should always be obtained from the landowner and/or occupier.
Information on conservation matters, including site ownership, relating to Sites of Special Scientific Interest (SSSIs) or National Nature Reserves (NNRs) in particular counties or districts may be obtained from the relevant country conservation agency headquarters listed below:
Countryside Council for Wales, Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd LL57 2DW.
Natural England, Northminster House, Peterborough PE1 1UA.
Scottish Natural Heritage, Great Glen House, Leachkin Road, Inverness IV3 8NW
Conserving our mineral heritage — JNCC policy statement
Sites that yield minerals are a key part of our natural heritage and a major scientific, educational and cultural resource. They are fundamental to understanding the character of ancient environments. The discovery, collection and study of minerals can be enjoyable and stimulating activities that give people a fascinating insight into the geological history of the Earth. However, the available mineral resource is finite. It is only through maintaining a prudent approach to the management of important mineral sites that future generations will be able to experience, study and enjoy them.
Responsible mineral collecting
In most circumstances, responsible mineral collecting is not harmful to the conservation of sites: it can actually benefit our understanding of geology. This is particularly true where the minerals are relatively common or the sites in which they are found are subject to high levels of natural or artificial degradation, such. as coastal cliffs that are being eroded, or quarries that are being actively worked. In such situations collecting mineral specimens that might otherwise be destroyed can be beneficial to science, provided that they are properly documented and made available for study. Responsible mineral collecting can therefore be a valuable activity in the sustainable management and safeguard of our natural heritage.
Irresponsible mineral collecting
Irresponsible collecting provides no scientific or educational gain and is therefore an unacceptable activity resulting in irreparable damage to our mineral heritage. It will pose a clear threat where minerals are rare or the mineral source is limited in extent, for example in a localized lode. Collecting without proper recording and curation, inexpert collecting, over-collecting and inappropriate use of power tools and heavy machinery are likely to reduce or even destroy the scientific value of such sites. Unless the activity is undertaken in an appropriate manner, the statutory nature conservation agencies, the Countryside Council for Wales, Environment and Heritage Service, Natural England and Scottish Natural Heritage, will oppose mineral collecting on the small number of Sites of Special Scientific Interest/Areas of Special Scientific Interest where this activity would cause significant damage to the features of special interest.
Code of good practice
Adopting a responsible approach to collecting is essential for conserving our mineral heritage. The basic principles set out below should be followed by all those intending to collect minerals.
Access and ownership — permission to enter private land and collect minerals must always be gained and local bylaws should be obeyed. A dear agreement should be made over the future ownership of any rock material collected.
Collecting — in general, collect only a few representative specimens and obtain these from fallen or loose material. Detailed scientific study will require collection of minerals in situ.
Site management — avoid disturbance to wildlife. Many invertebrates and lower plants live on or under loose rocks that should be replaced in their original positions whenever possible. Do not leave the site in an untidy or dangerous condition for those who follow.
Recording and curation — always record precisely the locality at which minerals are found and, if collected in situ, record relevant details of the position of the rock from where the mineral was collected. Ensure that these records can be directly related to the relevant specimens. Where necessary, seek specialist advice on specimen identification and care. Minerals of prime scientific importance should be placed in a suitable repository, normally a museum with adequate curatorial and storage facilities.
Management of our mineral heritage
In order to achieve the successful management of the mineral heritage of the United Kingdom, the statutory nature conservation agencies will:
- Promote the responsible approach outlined in the Code of Good Practice, above.
- Encourage the placement of scientifically important minerals into a suitable repository (such as a museum) in order to ensure their proper curation, longterm security and accessibility
- Recognize the contribution that responsible mineral collectors can make to geological and mineralogical study.
- Encourage collaboration within the geological community to ensure that maximum educational and scientific gain is made from our mineral resource.
- Support and encourage initiatives that increase awareness and understanding of the value of our mineral resource and the need to conserve it.
- Increase awareness and understanding of the differing management needs of mineral sites. In particular, encourage landowners and occupiers to become advocates for conservation of the mineral resource.
- Review the need for export and import controls on the international trade in mineral specimens.
JNCC, 1997
Preface
There is such a diversity of rocks, minerals, fossils and landforms packed into the piece of the Earth's crust we call 'Britain' that it is difficult to be unimpressed by the long, complex history of geological change to which they are testimony. But if we are to improve our understanding of the nature of the geological forces that have shaped our islands, further unravel their history in 'deep time' and learn more of the history of life on Earth, we must ensure that the most scientifically important Earth science sites are conserved for future generations to study, research and enjoy. Moreover, as an educational field resource and as training grounds for new generations of geologists on which to hone their skills, it is essential that such sites continue to remain available for study. The first step in achieving this goal is to identify the key sites, which is a primary aim of the Geological Conservation Review.
The GCR, formally launched in 1977, is a world-first in the systematic selection and documentation of a country's best Earth science sites. No other country has attempted such a comprehensive and systematic review of its Earth science sites on anything near the same scale. After three decades of site evaluation, consultation with the scientific community, and site documentation, we now have an inventory of over 3000 GCR sites, selected for 100 categories covering the entire range of the geological and geomorphological features of Britain.
The minimum criterion for GCR site selection is that sites should offer the finest and/or the most representative feature for illustrating a particular aspect of geology or geomorphology. The resulting GCR sites are thus, at the very least, of national scientific importance and many of these include features regarded as either 'classic' (i.e. a 'textbook example'), internationally important, or simply 'unique'. Some are, in addition, visually spectacular.
The present volume is the 36th to be published in the GCR series of books, which, when complete, will stretch to more than 40 volumes and provide a vast geoconservation information resource. This volume summarizes the considerable research that has been undertaken on the localities described and will be invaluable as an essential reference source for those engaged in their study and aims to provide a stimulus for further investigation. It will also be helpful to teachers and lecturers and for those people who, in one way or another, have a vested interest in the GCR sites: owners, occupiers, planners and those concerned with the practicalities of site conservation. The conservation value of the sites is mostly based on a specialist understanding of the Earth science features present and is, therefore, of a technical nature. The account of each site ends, however, with a brief summary of the geological interest, framed in less technical language, in order to help the non-specialist.
This volume deals with the state of knowledge of the sites available at the time of writing, and it must be seen in this context. There is still much to learn about the GCR sites documented here, in increasing our knowledge and understanding of geological history and processes. Geological studies, like any other science, are ever-developing, with new discoveries being made, and existing models being subject to continual testing and modification as new data comes to light. While the existing sites continue to enable us to add to our geological knowledge, increased or hitherto unrecognized significance may be seen in new sites. Indeed, during the writing of this volume, a number of additional localities were considered for inclusion and, after a period of assessment, were ultimately deemed to be worthy of GCR status and were included in this account. That fact is almost inevitable when one considers that some of the original networks of sites were drawn up over two decades ago.
Therefore, it is possible that further important sites will be identified in future years for the GCR as research continues. However, it must be stressed that the GCR is intended to be a minimalist scheme, with the selection of only the best, most representative, example of a geological feature, rather than the selection of a series of sites showing closely analogous features.
This account clearly demonstrates the value of the GCR sites to the study of mineralization and their importance within the wider context of Britain's outstanding scientific and natural heritage, and I am grateful to the authors for their perseverance and forebearance in the preparation of this book and their valuable contribution in assisting JNCC in its conservation goals.
N.V Ellis, GCR Publications Manager January 2010