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Following the Pennine chain of hills southwards from Weardale and Teesdale,
mining activity extends down into Yorkshire through Swaledale, Wensleydale
and Wharfedale as far as the area around Skipton and Pateley Bridge. From
a collector's point of view Yorkshire has been somewhat overshadowed by
its more famous northern neighbours. Yet it has produced some excellent
finds of fluorite and barite plus various secondary minerals including
ktenasite, gearksutite and otavite. It was predominately a lead mining
area producing an estimated 1,000,000 of lead concentrates. Small copper
deposits occurred on the periphery of the mining field as at the Richmond
mines but commercially deposits of zinc, fluorite and barite were largely
absent.
The deposits occur in Carboniferous rocks. Post Carboniferous uplifting
of the area between the Stainmore Trough and the Craven basin connected
with the Caledonian granite underlying Wensleydale providing the pattern
of fissures facilitating the vein channels.
In the east of Yorkshire large deposits of ironstone were worked in the
North York Moors but being a low grade replacement deposit little of interest
for the collector was ever found. A little to the north of Whitby the
relatively recent exploitation of the Zechstein evaporates at Boulby mine
has provided excellent specimens of borate minerals.
History
The finding of two pigs of lead near Greenhow with the stamp of Emperor
Domitian provides evidence of mining in Roman times and there is circumstantial
evidence that the Brigantes who occupied the Pennines at the time of the
Roman invasion worked the vein outcrops. The first recorded mining was
in 1145 at which time, Jervaulx Abbey had a grant to dig iron and leads
ore in Wensleydale. Until the 16th Century many of the mines were under
monastic ownership. Increased mining activity was in part driven by the
era of castles and monasteries building both in England and the continent
with the use of lead for waterproofing roofs and construction of gutters.
Yorkshire, along with other areas in England enjoyed a resurgence of mining
activity during the 16th Century with many mines operating although working
independently and on a relatively small scale. Monastic ownership diminished
after Henry VIII dissolution of the monasteries (1536-1540), large areas
of Yorkshire being sold by the crown or given away for services rendered.
Mineral rights and land ownership were usually common but subsequent sales
of one of the other meant that as time went on this was not always the
case.
From the 17th century on many of the mines consolidated into larger concerns
defined by geographical areas, the change driven by technological developments
which favoured larger operations often with the lessors taking a direct
interest.
The depression in lead prices brought about the end of significant mining
in the late 19th Century. Yorkshire did not have the large deposits of
zinc, fluorite and barite that enabled mining to the north in County Durham
and Cumberland to continue well into the 20th Century. The exception to
this was the Greenhow Hill area where fluorite was more abundant and in
the 1920's a water tunnel driven underneath the area by Bradford Corporation
discovered a number of hitherto unexploited veins.
Minerals such as calcite, barite, hemimorphite and galena are quite common
throughout the Yorkshire Pennines but are usually massive or micro crystalline.
Locations of particular or unusual mineralogical interest are: -
Some of the dumps contain a banded brown barite which, after cutting,
polishes well and resembles Derbyshire 'Oakstone'.
Clouds mine
A small mine on the periphery of
the area, noted for malachite and small crystals of azurite.
Dam Rigg Mine
Barite in aesthetic aggregated lustrous crystals with 'chisel' terminations.
From the nearby Danby Level specimens of classic tapered pseudo-hexagonal
witherite, perhaps the best from Yorkshire.
Great Sleddale Copper mine
Small, sharp azurite crystals with malachite. Well formed clear to amber
fluorite crystals to 15mm. See UK Journal of Mines & Minerals, issue
No.7 (1989).
Gunnerside Gill
1) Sun Hush Level
Good strontianite crystals up to 40 mm in groups up to 15 cm across with
small yellow fluorite cubes.
2) Priscilla Level
Radiating masses of white strontianite to about 1 cm associated with barite
and sphalerite. Small witherite crystals.
3) Sir Francis Level
Sprays of strontianite up to 20 mm. Good translucent calcite and pseudo-hexagonal
grey witherite to 25mm.
Hags Gill
Barite in well formed elongated crystals of a pale bluish hue.
Small crystals of amber and purple fluorite, azurite, barite and calcite.
Old Gang mine
1) Bunton Level
Strontianite, cockscomb barite and pseudomorphs of smithsonite after strontianite.
2) Hard Level
Good strontianite sprays to 15 mm on North Vein. Old Rake vein has produce
iridescent sphalerite on white cockscomb barite as well as white/grey
strontianite masses to 15 cm with individual crystals to 15 mm. In 2003
a sub-level produced the rare minerals ktenasite & gearksutite.
3) Brandy Bottle Incline
Some of the best Yorkshire cerussites have come from an area at the bottom
of the incline. Specimens show white platy individual crystals of good
lustre, the best specimens on iron stained barite. Other minerals found
are barite, hemimorphite, aurichalcite, siderite and witherite.
West Burton Area
Mines produced fine fluorite specimens with cubes up to 3 cms of a pale
purple colour.
Wet Grooves mine
Excellent specimens of barite showing many habits but predominantly chisel
shaped. Nearby a small openwork has produced both black and green barite
often coated with micro hemimorphite. Fluorite is common with clear to
pale yellow un-twinned cubes to 6cms. Calcite occurs in simple nail head
form and in more complex aggregated habits. Aurichalcite and smithsonite.
Whitaside Mine
Aurichalcite, aragonite, hemimorphite to 1 cm and yellow smithsonite.
Sharp pseudomorphs of goethite after marcasite on shallow dumps from nearby
trials.
Buckden Gavel mine
Beds of small but extremely lustrous hemimorphite. Brown smithsonite
balls to 1 mm and small but perfect barytocalcite to 2 mm.
Coldstones quarry
Quarry workings have cut through a number of mineral veins which have
produced excellent specimens of purple fluorite, nail-head calcite, barite,
hemimorphite and galena. Anglesite crystals up to 4 cms long and sharp
white blocky cerussite crystals. Otavite and Doyleite have also been found
here.
Duck Street quarry
A disused quarry where large fluorite cubes, calcite and mimium have been
found.
Elbolton mine
Some excellent fluorite specimens have recently been available with clear
centres and well defined purple edges.
Gill Heads/Trollers Gill.
Known for distinctive clear fluorite cubes up to 3 cms with strongly coloured
purple edges.
Merryfield Mine
Excellent 'Old-time' strontianite specimens were found here.
Pale yellow fluorite with sulphide inclusions.
Just outside the map area, the Conoley lead mine near Skipton produced
excellent specimens of cerussite but rarely come onto the market now.
During road widening on the A1 trunk road near
in the early 1990's mineralised pockets were found in the Magnesian limestone
containing barite, calcite and goethite pseudomorphs after pyrite.
Beach boulders have occasionally produced sharp lustrous rosettes and
rhombs of calcite with rarely a little barite.
The South Bay at Scarborough is the type locality for both scarborite
and hydroscarborite. However, neither would win any prizes for aesthetics!
Note-For any of these localities permission must be sought before visiting
and never enter old mine workings.
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