An
Introduction to the Minerals of |
Introduction including
photographs of |
|
Introduction Alston Moor, in north-east Cumbria, on the northern edge of the Pennines, was formerly a major lead-zinc orefield during the 19th century. It has yielded fine, collector specimens of both common and rare mineral species from that period up to the present day, despite it no longer being active as an ore producer. Just a few
miles farther east, in County Durham, Like Alston Moor, ore was extracted in the past. In the case of the Weardale mines, fluorite and latterly barite were important ores. Despite the closure of the Weardale mines, a new development of great interest to collectors, is the working of some of the mines on a commercial basis for specimens. The extraction of fine fluorite specimens is taking place at the Rogerley Mine - thanks to a recent commercial venture (see below) and also at the Greenlaws Mine. ALSTON MOOR, Cumbria This area lies predominantly in the county of Cumbria, but the orefield stretches into the edges of the neighbouring counties of Durham and Northumbria. The main centre of mining activity was around Nenthead where there are a number of mines: Smallcleugh, Capelcleugh, Scraith Holes, Nentberry Haggs, Settlingstones, Fallowfield and Brownley Hill being amongst the most well-known. |
GALENA
SPHALERITE |
Several of these mines have yielded excellent specimens of the more common species, such as galena, calcite and sphalerite. These minerals are synonymous with the area. However,
the Alston Moor area is also the type locality for the
minerals barytocalcite, witherite and alstonite: a fact
which gives the mines of the area and their minerals The type locality minerals are less common, but the area has yielded some of the best examples known for these species - and occasionally in recent finds made by collectors. Also in recent times, an increasing number of secondary species have been recorded by collectors. One of these minerals, briangyoungite, has its type locality in the area, being first described from the Brownley Hill Mine, where it occurs as minute crystal aggregates. |
WITHERITE
- Nentberry Haggs Mine,
Nenthead, Alston Moor, Cumbria. |
BARYTOCALCITE |
ALSTONITE |
| WEARDALE,
County Durham There are several classic localities in the Weardale district of great interest to collectors. The specimens of fluorite in particular which they produced adorn the finest mineral collections in the world. The most famous mines
that produced fluorite as specimens - Apart from the variety of colours, aesthetics and the often well-sized crystals from these and other localities in the area, Weardale fluorites have the additional attraction of their renowned, strong fluorescence - normally a brilliant lilac colour. Other than fluorite from these mines, perhaps of special note as collector specimens is pyrrhotite from Cambokeels Mine. Galena, sphalerite and calcite - often as good crystals - are also frequently associated with the fluorite of the Weardale mines. |
FLUORITE - Frazer's Hush Mine, Rookhope, |
FLUORITE
- Greenlaws Mine,
St. John's Chapel, |
FLUORITE
- Heights Mine, Westgate, |
The Rogerley Mine In the
summer of 1999, an American consortium, The consortium were in search of the mine's well-known, typical, rich green cubic fluorite crystals which, in the best examples, often display a strong, daylight fluorescence! Since then, numerous good specimens of both green and purple crystals have been extracted from several newly-discovered mineralized pockets. These results can now be seen at most major mineral shows and mining activities are ongoing. |
FLUORITE - Rogerley Mine, Weardale. |
| A detailed
and graphic account of the specimen extraction so far,
the background and the history of the mine can all be
viewed by visiting www.ukminingventures.com The site also has a section for specimen purchases. |
*ACKNOWLEDGEMENT: This website would like to
express its sincere thanks to Jesse Fisher of UK Mining
Ventures for the photograph of Rogerley fluorite (above) |
the end
References/ Further Reading
Rocks & Minerals
vol. 75, no.1, pp 54-62; The Rogerley Mine, Weardale, County
Durham, England (J. Fisher & L. Greenbank) (2000)
UKJMM (United Kingdom
Journal of Mines & Minerals)
vol. 22, Twenty Years In Minerals: Northern England.
North Pennines, pp. 25-42. (D.I. Green & P.J. Briscoe).
(2002).
vol. 23, The Rogerley Mine, Weardale, County Durham, England. pp.
9-20. (J. Fisher & L. Greenbank). (2003).
Mineralogical Record
vol. 13, no.1, The Boltsburn Mine, Weardale, County
Durham, England (R. J. King). (1982)
vol. 31, no.3, The Brownley Hill Mine, Alston Moor District,
Cumbria, England. (D.I. Green, D. McCallum & M. Wood). (2000)
© Minerals of Scotland - 2008