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Click on a title below to view the abstract
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EDITORIAL: BRITISH MINERAL SHOWS |
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FORCE CRAG MINE |
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MINERAL NOTES
John Betterton - David Green - Christine Hacker - Mike Merry - Steve Rust - Norman Thompson |
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ROYAL CORNWALL MUSEUM
Roger Penhallurick |
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YSTRAD EINION MINE
John Mason - Steve Rust |
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SUSSEX MINERAL AND LAPIDARY SOCIETY |
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MINERAL NEWS |

48 pages, 10 colour.
A suite of supergene minerals from a small oxidised area of the galena-sphalerite-barite
orebody at Force Crag Mine is described. Species present include pyromorphite,
cerussite, silver, acanthite and a number of rare Cu, Pb, and Zn sulphates.

Brown pyromorphite crystals to 10 mm on a brecciated wallrock fragment.
Stilpnomelane from Penberthy Croft mine a second Cornish occurrence
John Betterton
Schulenbergite from Nentsberry Haggs Mine, Cumbria
Norman Thompson
Wulfenite from Wheal Ludcott, Cornwall
David Green - Mike Merry
Chenite from Esgait Hir Mine, Talybont, Dyfed
Steve Rust
Rutile from Wheal Remfrey China Clay Pit, Indian Queens,
St. Enoder, Cornwall
Christine M. Hacker
Symplesite from Sandbeds Gill Mine, Cumbria
Norman Thompson
The Royal Cornwall Museum houses perhaps the finest regional mineral collection in the British Isles.
It includes the world famous Philip Rashleigh collection, which contains many exceptional Cornish mineral specimens, as well as minerals from classic localities elsewhere in Britain and abroad.

Azurite (41 mm across) on quartz. This specimen is figured in Sowerby (1804, table XCIV). The accompanying description reads:
"The present specimen is a very rare and curious modification of carbonate of copper. At present I only know of two specimens; one belonging to P. Rashleigh, Esq., and the other in the possession of Mr. R. Phillips.
The upper figure which belongs to the former gentleman is, as he observes, remarkable for being on the broken end of a large milky rock crystal ..."
Ystrad Einion mine is a small working situated near Machynlleth, in the Central Wales Orefield.
Several distinct phases of primary mineralisation can be distinguished. Supergene oxidation has given rise to a suite of copper, lead, zinc and iron secondary minerals. Most of these appear to have formed by post-mining oxidation processes. The post-mining mineral suite includes the rare minerals schulenbergite and ktenasite, and the first Welsh occurrence of beudantite.

Serpierite rosettes to 5 mm, collected underground at Ystrad Einion mine. Steve Rust collection.
Agate Microstructure and Possible Origin
by Trevor Moxon (1996)
David Green
Laurion The Minerals of Ancient Slags
by Piet Gelaude, Piet van Kalmthout and Christian Rewitzer (1996)
Trevor Wolloxall
Minerals of South Africa
by Bruce Cairncross and Roger Dixon (1995)
David Green