THE
WEST CUMBRIAN IRON OREFIELD by Wendell E. Wilson & Thomas P. Moore
INTRODUCTION The West Cumbrian Iron Orefield is not a name familiar to many collectors as a “classic” locality. However, the names Frizington, Egremont and Cleator Moor immediately conjure images of fabulous, classic barite, calcite and fluorite crystal clusters, mammillated to reniform hematite “kidney ore” specimens, and beautiful, lustrous, colorless to smoky quartz crystals of a stout habit on sparkling drusy hematite. In the decades following 1830 and into the early 20th century, when the mining of red hematite iron ore flourished in West Cumbria, the region was one of the world’s most prolific mineral localities. It produced specimens of barite, fluorite, and calcite by the thousands; some say that the finest of the region’s calcite specimens have never been equaled for beauty by calcites from any other locality in the world. HISTORY Ancient slag heaps near known deposits are evidence of iron working, perhaps as long ago as Roman times or even earlier. The earliest record of iron mining in Cumbria is a Royal grant for an iron mine near Egremont given in 1179 to the Holme Cultram Abbey. Iron ore was being mined at Bigrigg continuously from 1635 to 1701, and in the last years of the 17th century was being shipped by boat to the iron smelter in the Forest of Dean. New furnaces were built periodically thereafter, at Langdale, Parton near Whitehaven, Maryport and Seaton. Mines were opened one after another, and by the end of the 18th century over 20,000 tons of hematite per year were being shipped from Cleator Moor to the Corran Foundry in Scotland. The mid-19th century saw even larger-scale production, but by the end of the century many of the mines had closed or had greatly reduced their output. By the 1920s only a few of the older mines were still in operation, though newer mines such as the Florence and the Beckermet were still going strong. The last mine to be opened in the district, the Haile Moor mine, was started in 1939. The newer mines were located south of Egremont, where the productive Carboniferous limestone horizon is concealed beneath a cover of Permo-Triassic rocks. MINES Beckermet Mine The Beckermet mine was opened in 1903, and eventually developed into an extensive collection of underground workings
extending nearly a mile and a half to the south. The discontinuous mineralization manifested itself as a series of orebodies controlled by several northwest-trending faults. Ultimately the Beckermet workings connected underground with those of the Florence and Ullcoats mines. In 1982, it was the last to close of the major hematite mines in western Cumbia. The Haile Moor mine was sunk in 1939 just a mile east of the Beckermet mine, and was the last mine to be opened in the district. It closed in 1973. The Haile Moor and Beckermet mines produced a substantial number of fine specimens of hematite, quartz, calcite and barite. Unlike in the other mines, however, the mining company considered mineral specimens to be company property, not a miner’s perquisite. Specimens were collected by the company and marketed to mineral dealers from the company offices at Workington. The Beckermet mine orebodies were not known for producing calcite specimens until the early 1970s when a very long fissure in the limestone above the lower orebodies was encountered at around 400 meters depth in the Beckermet section of the joined FlorenceBeckermet underground complex. It contained a zone of pockets that miners named the “Banana Slide Fault” because of the huge sloping piles of wet, greasy, iron-stained rubble stacked below it. This fissure, which extended for about 1.6 km, was lined with hexagonal prismatic calcite crystals toward one end and sharp scalenohedral calcites towards the other, all colored red from included hematite. To collect specimens, miners entered the fissure from below and then worked above the rubble. To descend and exit, one had to suffer a wet and slippery 45-meter slide (preferably on soft sacks) down the piles of rubble and back to the haulage level (personal communication from mine surveyor Raymond Clements). Specimens from this find are easily distinguishable from classic 19th century Cumbrian calcite specimens, which typically show thick, pellucid, colorless, scalenohedral crystals or butterfly twins. By contrast, Banana Slide specimens are clusters of thin calcite crystals to 10 cm long, either coming to points or showing trigonal “nailhead” terminations; the crystals are stained red by hematite inclusions, and many show complex red or black phantoms caused by finely divided hematite and/or manganese oxides. The crystal groups reach large-cabinet size. After the mines closed in 1982, a group of former employees organized to conduct small-scale mining of a near-surface deposit called the Lonely Hearts orebody; work there continued until 2007, and some fine specimens of hematite with blue fluorite were recov-
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