A map of the Weardale region, including Rookhopeburn showing major mineralized veins and important specimen-producing mines. Map by Bill Besse.

Blackdene Mine

The site of the Blackdene mine is located just north of the River Wear, between the villages of St. John's Chapel and Ireshopeburn. Lead mining on many of numerous veins in this area dates back to medieval times, and Fairburn (1996) reports that the first records of mining leases on the site date to 1401. During the mid to latter part of the twentieth century, the property became one of the most productive fluorspar mines in the dale. The Blackdene mine proper was originally developed by the Beaumont Company in the early nineteenth century for lead. The main level followed the Blackdene vein northeastward from near the banks of the River Wear, and eventually intersected the workings of the adjacent Elmsford level. Dunham (1990) reports that between 1818 and 1861 14,198 tons of lead concentrates were produced from the combined workings. Production continued into the 1880s, but like most lead mines in the region, it shut down around this time.

A deep purple twinned fluorite crystal, 2.2 cm on edge, on a cluster of smaller opaque fluorites. From the workings on the Blackdene Vein ca. 1965.

The mine was reopened for fluorspar in 1908 and worked by a succession of owners on both the Blackdene and Slitt veins. The mine was shut down in 1939 because of excessive subsidence. In 1949 the property was acquired by United Steel Companies, which began extensive exploration and development on the Blackdene, Silverdykes and Slitt veins at levels between the Three Yard Limestone to below the Scar Limestone. By 1973 commercial reserves on the Blackdene vein appeared exhausted, and a new incline was driven to access unmined portions of the Slitt vein. It was during this period that the mine produced many of the specimens seen today. With nationalization of the steel industry in the 1960s, ownership of the mine passed to British Steel, but it was disposed of when the industry crashed in 1982. Weardale Mining and Processing continued to operate the mine until 1987, when it was finally closed. The flotation mill at the site was sold for scrap and dismantled in the mid-1990s. Most of the mine is now inaccessible because of flooding and collapse and the site has been completely reclaimed.

A cluster of fluorite crystals on galena, with minor chalcopyrite. From workings on the Slitt Vein in the 1970s. 7x6x5 cm overall size.

The Blackdene mine is best known for its production of medium to dark purple fluorite crystals, associated with lustrous galena crystals of complex habit. Other common associations include calcite, chalcopyrite, and quartz. Smaller fluorite crystals (to 5 centimeters) are frequently lustrous and transparent, where-as larger ones are usually opaque. These larger crystals are sometimes elongate, giving them a tetragonal rather than cubic appearance. Fluorite crystals in varying shades of yellow and green have also been found in the mine, and the rarest are combinations of the two. Well-formed calcite in a variety of forms was found as well. The best specimens from the mine probably came from the recent workings on the Slitt vein.

A twinned yellow fluorite crystal, 2.5 cm across with a faint green core, on a quartz matrix. From the Blackdene Mine, Slitt Vein.

A cluster of untwinned, bicolor fluorite crystals with a partial overgrowth of calcite. From workings on the Slitt Vein in the 1970s. 9x5x5 cm overall size.

Cambokeels Mine

The Cambokeels mine (sometimes called Cammock Eals) was developed on a section of the Slitt Vein roughly halfway between the villages of Eastgate and Westgate. The main adit is located on the north banks of the River Wear, and the abandoned workings can still be seen from the road (A689). The Slitt vein in this area was first worked by the Beaumont Company between 1868 and 1871 for lead. Although the vein was large, lead values were poor and the mine was soon abandoned. The mine was reopened for fluorspar in 1905 and was worked on-and-off by a succession of owners through much of the twentieth century.

Several colorless penetration-twinned fluorite crystals, up to 2.5 cm on edge, on white crystalling quartz. Recovered in 1988 from the Zinc Flats, 320 level.

The most recent production cycle at Cambokeels began in the early 1970s, and for the next decade and a half the mine was one of the most productive sources of fluorite in Weardale. Malcolm, Brown and Madison acquired the mine in 1973 and put in a new incline below the old Horse level, discovering high-grade fluorite ore from the 40 meter level down. The mine was sold in short order to Swiss Aluminium UK (SAMUK), which established working levels at 200 meters (in the Tynebottom Limestone) and at 240 meters (in the Whin Sill and Jew Limestone). When SAMUK ceased operations in the mid-1980s the mine was acquired by Weardale Mining and minerals, a subsidiary of Minworth, Ltd., which established levels at 280 and 320 meters, and had reached the 340 Level by the time the mine closed in 1989. Cambokeels was the deepest mine in the region, and had work continued, it undoubtedly would have accessed the unexposed Weardale Granite. Currently, all levels are flooded and and the site has largely been cleared.

A group of lavender/purple twinned fluorite crystals on quartz, 12x9x6 cm overall size. Recovered from a single pocket at the 340 level in 1989, shortly before the mine closed.

Fluorite from the upper levels of the mine usually occurs as twinned crystals of pale/pastel shades of purple. In the last years of production a couple of notable specimen finds were made. In 1987 numerous specimens of twinned, transparent, colorless to pale aqua-blue fluorite associated with quartz and sulfides such as pyrite and pyrrhotite were recovered from the Zinc Flats at the 320 level. The flats at this level were rich in sphalerite but yielded few specimens as it was mostly massive. This area of the mine was also so rich in crystal-lined cavities that the mining crews had great difficulty drilling and loading holes for blasting (D. Beadle, pers. com., 2002). In 1989 a single cavity from the 340 level produced some fine specimens of twinned, gemmy lavender-colored fluorite on a white quartz matrix. The lower reaches of the mine were also sulfide-rich, and some of the best pyrrhotite crystals from Britain were found there. Calcite was widespread throughout the mine, and specimens of numerous habits were recovered.

Fluorite with calcite on quartz, 14x10x7 cm overall size. Specimen was likely recovered from the 200 Level in the early 1980s.

Eastgate Cement Quarry

The Blue Circle (or Eastgate) Cement quarry worked an exposure of the Great Limestone on the south side of the Wear River, between the villages of Eastgate and Westgate. Prior to demolition, the smokestack of the kiln was a valley landmark, and the large, bright yellow trucks from the plant have been a constant source of excitement to motorists along the narrow road through the dale for many years. The quarry began operation in the mid 1960's and is the third major source, along with the Heights quarry and Rogerley Mine, of green fluorite in Weardale.

A large, well formed, dark green penetration twinned fluorite crystal, 2.5 cm on edge, from the Eastgate Cement Quarry.

Fluorite crystals from the Cement quarry are often paler green than either the Heights or Rogerley and usually have a purplish-gray cast because of internal purple color zones. On rare occasions yellow and purple fluorite have also been found. Specimens are sometimes encountered during quarrying activities, and through the years have come out in small numbers courtesy of enterprising quarry employees and clandestine weekend collectors.

Mineralization in the quarry has never been studied, and Dunham (1990) makes no mention of it. Visitors to the quarry have reported that fluorite-containing cavities occur near the top of the Great Limestone (High Flats horizon), associated with a mineralized vein that may be an unmapped extension of the Heights West Cross vein on the south side of the River Wear.

The Blue Circle cement processing plant in 2004. The plant with its tall smokestack was long a valley landmark, but has since been demolished.

In 2001 the quarry operation was purchased by the French cement manufacturer La Farge, which announced its intention to cease operations in the quarry and dismantle the processing plant. The plant was shut down in 2002 and demolished during the summer of 2005. The mineralized veins within the quarry have also been buried during site reclamation, and are no longer accessible.

A cluster of rare yellow fluorite crystals up to 2.0 cm on edge, from the Eastgate Cement Quarry.

Heights Mine and Quarry

The Heights mine is located to the north of the River Wear, between the villages of Eastgate and Westgate. The Heights mine proper consists of numerous underground workings that were developed on three principal veins - the roughly parallel Heights North and South veins and the intersecting West Cross vein. Most of the workings were developed to access the associated flats at the High Flats horizon in the Great Limestone.

Though some lead was obtained from the flats by the Beaumont Company during the early 1860s, the Heights mine was principally worked by the Weardale Iron Company between 1850 and 1868 as a source of iron ore. Commercial iron deposits were found in the flats surrounding the veins as limonite derived from the oxidation of iron carbonates (ankerite and/or siderite). The flats associated with the three main veins occur primarily at the High Flat Horizon near the top of the Great Limestone. These flats are quite vuggy and have been the source of some magnificent specimens of twinned emerald-green fluorite, in crystals up to 4 centimeters. Well-formed specimens of pale purple to colorless fluorite have also been found. Associated minerals include galena, calcite, and aragonite. Larger, opaque green fluorite crystals to 8 centimeters have also been encountered

Green, twinned fluorite crystals to 1.5 cm across, on limonitic limestone matrix, from the Heights South Vein.

The old underground workings, long a source of specimens dug by amateur collectors, were in dangerous condition and were sealed in the late 1970s (Bancroft 1984). In recent years the area surrounding the original mine has been developed as a quarry for crushed stone and as quarrying progressed, portions of the South and West Cross veins were again exposed. During the 1990s the quarry management would on occasion allow limited access to collectors, and specimens once again emerged from this famous mine.

Pale purple, twinned fluorite crystals, to 2.5 cm across, from the Heights West Cross Vein

Specimens have occasionally shown up on the market recently, labeled as coming from the “Heights Park mine.” It is likely that these have come from the nearby Park Burn level. This level is located just south of the Heights mine and was begun by the Beaumont Company in 1861 to access the Slitt vein in the Natrass Gill Hazel in search of lead. This level was eventually extended to the Heights South vein but proved uneconomic (Dunham 1990). Another level, known as the Heights Pasture mine was developed between 1905 and 1918 for fluorspar on the Slitt vein above the Park Burn level.

A cluster of twinned green fluorite crystals with calcite on ironstone matrix. 8 cm across. From the Heights North Vein.

Rogerley Mine

The Rogerley mine is located in an abandoned limestone quarry of the same name, between Stanhope and Frosterley, just north of the River Wear. The mine works a small north-south trending vein (known as the Greenbank Vein) and associated flats at the High Flats horizon in the Great Limestone by means of a small network of underground tunnels driven from a platform carved into the quarry face some 50 feet (15 meters) above the quarry floor. The quarry itself was operated during the mid-nineteenth century for limestone, which was used as a flux at local iron foundries. There is no evidence that the quarry was ever worked for lead or fluorspar, most likely because the overall grade of the ore deposit is low. When encountered, the mineralization was simply considered an impurity in the limestone and discarded in a series of now overgrown tailings piles on the south side of the quarry.

Early workings at the Rogerley by Cumbria Mining and Mineral Co.

In the early 1970s the existence of high-quality fluorite specimens coming from the quarry prompted local collectors Lindsay Greenbank and Mike Sutcliffe (operating as Cumbria Mining and Mineral Company) to arrange leases for the mineral rights and establish what is, to this day, the only commercial mine in the Britain operated solely for specimens. The mine was worked on weekends by the partners through the early 1990s, producing a limited but steady stream of high-quality green fluorite specimens. Health problems forced the Lindsay and Mick to retire from mining in 1996, afterwhich leases were taken over by a new partnership, UK Mining Ventures. Mining at the Rogerley resumed in May 1999 and continued a the mine each summer through 2016. During this time over 300 meters of new tunnel was driven and a relatively steady production of specimens of bright green fluorite was maintained. For more information on operations at the Rogerley Mine during this time period, please see the The Rogerley Archieves pages. In the summer of 2017 operation of the mine was taken over by Crystal Classics.

The UKMV crew with Eimco at the Rogerley Mine portal in 2001. Left to right: Lofty, Dave, and Byron.

Mineralized cavities are found in two distinct areas of the Rogerely mine: (1) in the vertical mineralized vein along which the original tunnel was driven and (2) in the metasomatic flats that extend laterally from the vein. To date, the current operators have concentrated on the flats, which have been the source of numerous attractive specimens of emerald green fluorite. Individual transparent crystals to around 3 centimeters in size occur, some of which have purple cores or thin zones of pale yellow near the surface. Small, crudely formed cuboctahedral crystals of galena are commonly found associated with the fluorite. Larger fluorite crystals (to 10 centimeters), both green and purple, have come from cavities in the vein, though these are usually opaque and untwinned.

Specimens recovered from the Blue Bell Pocket, during the summer of 2009.

A second, east-west trending vein, the Sutcliffe vein, is exposed in a western extension of the Rogerley quarry and it is likely that this vein intersects the north-south vein somewhere to the north of the current workings. A limited amount of surface work was done on this vein in the mid-1970s, and some very attractive specimens of green and purple fluorite were recovered. Upon taking over the operation, the Sutcliffe Vein exposure was the first focus of mining by Crystal Classics, who have named their workings the "Diana Marie Mine." Surface excavations during the summer and autumn of 2017 uncovered a sizeable pocket, which yielded material similar to that found in the 1970s. Current plans are to establish a portal on the vein and continue mining and exploration underground.

The West Rogerley Quarry in 2002. The Sutcliffe Vein is in the promintory extending from the quarry wall.

Greenlaws Mine

The Greenlaws mine complex is located approximately one kilometer south of St. John's Chapel at Daddry Shield. Two parallel veins, the Greenlaws East and West, were accessed by the mine, but the East Vein appears to have been far more productive. The first work in the area appears to have been some medieval-period hushing on the West Vein. The Greenlaws East vein was worked by the Beaumont Company between 1850 and 1884 for lead, and for a short period around 1860 it ranked as one of the major lead-producing mines in Weardale. After the 1882 lead market crash the Beaumont Company gave up the mine, along with its other holdings in the area. The lease was picked up by the Weardale Lead Company in 1884, and low-level work was done until 1897. The workings ultimately accessed levels from the Little Limestone down to the Tynebottom Limestone from at least three portals. Attempts to reopen the mine in the 1940s for fluorspar were reportedly unsuccessful, and with the exception of some recent small-scale specimen recovery the mine has been idle since that time.

A stone arched portal at the Middle Level of the Greenlaws Mine.

Dunham (1990) reports the presence of a small belt of cavity-bearing flats adjacent to the Greenlaws East vein at the High Flats horizon in the Great Limestone, along with some in the upper portions of the Scar Limestone. Specimens of purple and rarely amber fluorite have come from the mine and are still occasionally encountered in older collections. During the early 2000s a group of collector/dealers recovered some well formed, dark purple and occasionally amber- colored specimens of untwinned fluorite from these flats. Access was gained by roping down an old shaft, but a change in property ownership put an end to the project in 2006. More recently, another group of collectors has rehabilitated a shaft higher up on the moors and gained access to a section of flats at the High Flats Horizon of the Great Limestone. Despite continuing logistical problems, a limited number of specimens have shown up at British and Continental mineral shows over the past few years.

A cluster of yellow and purple fluorite crystals, up to 4 cm, overgrowing a mound of smaller purple fluorites, from the Greenlaws Mine, East Vein. Specimen dates to the latter 19th century and was formerly in the collection of Professor Harry Harwood, Manchester University.

West Pasture Mine

The West Pasture mine accesses the West Pastures vein, which is located on the eastern side of Stanhopeburn, approximately 2 kilometers north of Stanhope. Details of the history of the mine are scarce, but it is located near the Stanhopeburn mine, which worked the eastern end of the Red vein first for lead, then fluorspar until the late 1970s. Dunham (1990) describes the West Pastures vein as an eastern branch of the Red vein, and work on the West Pastures may have been related to activity at the Stanhopeburn mine. He states that the West Pastures vein has been worked eastward from Stanhopeburn for 1,850 feet (564 meters) in the Great Limestone, where flats of a limited extent have yielded a small quantity of lead ore. Unfortunately, no further details are given.

Apple-green, untwinned fluorite crystals, up to 2 cm across, on a crust of galena and limonite from the West Pastures Mine.

Green and Briscoe (2002) reported that the mine was briefly reopened in the 1970s by the property owners to recover large “decorator” specimens for their homes. When first recovered, West Pasture fluorite is often an attractive apple-green color. Unfortunately, this quickly fades to an unattractive shade of purplish-gray with exposure to sunlight, and only specimens stored in cabinets are likely to have retained their original color. Though in poor condition, the mine was accessible until just recently, and was a popular destination for local collectors, who have recovered numerous specimens of fluorite from flats in the Great Limestone in recent years. Crystals are usually untwinned and often occur on a galena and/or sphalerite crust.

White's Level, Middlehope

During the early to mid 19th century several lead mines were active along Middlehopeburn (“burn” is a local term for a stream valley), to the north of the village of Westgate. In 1818 one of these mines – the Middlehope Shield Mine, accessed by White’s Level – was the site of possibly the earliest major specimen find to be recorded in the region. In the “Annals of Philosophy”, vol. XIV, published in 1819 is a short paper by Edward Daniel Clarke, (then Professor of Mineralogy at Cambridge University) entitled “Account of a newly discovered variety of green fluor spar, of uncommon beauty, with remarkable properties of colour and phosphorescence.” In this paper, he describes a large find of “perfectly transparent, intense emerald green” fluorite that occurred at the Middlehope Shield mine, near Westgate, in the autumn of 1818. He goes on to give a description of the specimens, noting the crystal twinning, beveled edges, surface “laminae”, and buff-colored, often friable matrix.

The portal to White's Level, Middlehope, in 2003. Though active during the lead mining period in the 19th century, the Middlehope mines were not reworked for fluorspar during the 20th century, and most are now protected archeological sites.

Specimens matching Clark’s description can be found to this day in many major museum collections, and occasionally for sale in the mineral marketplace. Unfortunately, most of these specimens have been mislocated and are commonly attributed to the nearby and better known Heights Mine. While both mines (as well as the Eastgate Cement Quarry and the Rogerley Mine) are known for green fluorite, the characteristics described by Clark set these specimens apart from those of the others. In particular, the matrix composition is distinctive in that most specimens from the Heights, Cement Quarry and Rogerley occur on a dense, dark brown ironstone or a hard, silica replaced limestone rather than the buff-colored friable material typical of White’s Level. In addition, the green color of many White’s Level specimens has faded because of their exposure to daylight over a long period of time (Fisher, 2005).

Twinned green fluorite crystals to 2 cm across, on a tan-colored sandy matrix from White's Level. Specimen was formerly in the Philadelphia Academy of Science collection.

Burtree Pasture Mine

Located in upper Weardale, just north of the village of Cowshill, The Burtree Pastures Mine was perhaps the single richest lead mine in the region. Mining on the site is believed to date back to the 15th century (Fairburn, 1996), but development of the present mine began after the property was acquired by the Beaumont Company around 1815. Between 1818-1883 extensive underground workings were developed following the Burtree Pasture vein, penetrating into the Whinn Sill and northeast toward Rookhope for a distance of almost 3 km. Dunham (1990) cites a production of almost 150,000 tons of lead concentrates from the mine during this time period. With the collapse of the lead market, the Beaumont Company ceased operation in 1883, though mining was continued at the site until 1890 by the Weardale Lead Company.

The Burtree Pasture Mine near Cowshill, upper Weardale. Photo likely dates from the late 19th century.

The mine was reopened in 1970 by Weardale Minerals (now owned by ICI) for fluorspar, appreciable amounts of which were believed to have been left in place during the previous lead mining operations. Unfortunately, attempts to reach the lower levels in the mine by rehabilitating the main shaft were not completely successful, and in 1977 the operation was acquired by Swiss Aluminium UK (SAMUK). Instead of trying to reach the lower workings, SAMUK drove a new decline from the near-surface Horse Level into the Great Limestone in an attempt to recover fluorspar remaining in the upper workings. Dunham (1990) reports that 47,200 tons of crude ore was produced, but evidently the fluorspar content was fairly low and the project was abandoned as uneconomical in 1981.

Main portal of the Burtree Pasture Mine during the SAMUK period in the 1970s.

Despite the prodigious output of the mine, particularly during the lead mining phase, specimens identified as coming from the Burtree Pastures Mine are relatively scarce. Dunham (1990) notes the existence of a small section of flats at the High Flats horizon of the Great limestone, which contained purple fluorite, quartz, iron carbonates and calcite. It is likely that most specimens known from the mine came from these flats during the SAMUK period of operation.

A cluster of purple fluorite crystals with minor siderite and quartz from the Burtree Pasture Mine. 14 cm across, recovered around 1974.

Sedling Mine

Several mineralized veins converge in the area around the Burtree Pasture Mine, and numerous mines, hushes and surface workings have turned up much of the area over the past several centuries. Heading eastward toward Middlehope is the Sedling vein, on which the Sedling Mine is located. Fairburn (1996) cites records of mining on the site as early as 1720, but like many other lead mines in the area it was acquired by the Beaumont Company in the early 19th century, and operated by them until around 1878. The mine was then taken up by the Weardale Lead Company, working it first for lead and then fluorspar until closure in 1948. Exploratory drilling was done on the vein by both SAMUK and Weardale Lead during the late 1960s and early 1970s, but it appears that the results were not encouraging as no further development was undertaken by either company.

Dunham cites a total fluorspar production of 166,421 tons between 1900 – 1948, and states that the mine was the principal fluorspar producer in the district during that time. Despite this, known specimens from the mine are scarce, though examples exist in the Russell collection at the Natrual History Museum, London. Dunham (1990) makes no mention of any flats associated with the Sedling vein, which may account for the paucity of specimens.

Purple fluorite crystals, both twinned and untwinned, on quartz, with minor galena, from the Sedling Mine. An old label from the Mineral Department of the British Museum indicates that the specimen was collected by Sir Arthur Russell in 1924.