Wheal Jane (Falmouth Consolidated Mines), Baldhu, Kea, Truro, Cornwall, England, UK

Latitude & Longitude (WGS84):	50° 14' 53'' North , 5° 6' 36'' West
Latitude & Longitude (decimal):	50.24831,-5.11009
UK National Grid Reference:	SW783434
Other regions containing this locality:	Devon and Cornwall metalliferous mining district, England, UK
Köppen climate type:	Cfb : Temperate oceanic climate

An old tin and copper mine, which also produced minor amounts of arsenic, lead, zinc, tungsten, silver, pyrite and ochre. The mine is said to have already been in operation in 1740. It closed around 1875, but tributers continued work above adit at a small scale until 1893. In 1906, Falmouth Consolidated Mines were formed by amalgamation of Wheal Jane, West Wheal Jane, Wheal Widden and Nangiles Mine. Falmouth and Sperries Mine (together with Wheal Hope and East Wheal Falmouth) was also included, but not much work was done in that sett. Operations concentrated in Wheal Jane and West Wheal Jane sections. After the group was dissolved in 1916, tributers continued working the Wheal Jane section until 1919. In 1939, Wheal Jane and West Wheal Jane were taken over by Mount Wellington Mine. Some exploration work was carried out in West Wheal Jane section, followed by the retimbering of Beecher's Shaft and commencing a crosscut to access the tin reserves that had been proven north of it. Though, when Mount Wellington Mine closed in 1941, this project had not been finished.

In the mid 1960s, the mines were acquired by Consolidated Gold Fields Ltd. During the following years, intensive exploration works were carried out, and in 1969, it was decided to re-open them under the name Wheal Jane. Clemow's Shaft of West Wheal Jane section (SW772426) was widened and deepened, and a new shaft (No. 2 Shaft) was sunk to a depth of 366 m. Subsequently, an underground crusher station was constructed and full surface support services were installed. The initial production covered 10% of the UK's tin consumption, saving £4 million a year in imports. When the project was re-evaluated during the 1970s, Consolidated Gold Fields Ltd found it uneconomical and with the threat of closure, the government paid to keep the pumps working. The mine was subsequently sold to Carnon Consolidated Ltd, a subsidiary of Rio Tinto Zinc, who redeveloped the mine and the mill. Later on, the company passed its commitment to a management consortium. In 1991, the mine was found to be unviable and the pumps were switched off.

There is a difference between the modern mine and the old mine in that modern Wheal Jane includes all of the mines of the former Falmouth Consolidated group, whereas old Wheal Jane represents its northeastern section only. As a consequence, specimens collected at Wheal Jane in relatively modern times may come from any of the mines in the sett (unless otherwise noted), whereas only the very old specimens come from Wheal Jane proper. For the same reason, a separate list of minerals for old Wheal Jane is impossible to compose, and we also have not created a separate entry for the old mine in the database. The grid reference, however, refers to old Wheal Jane. The buildings of the modern mine are located between West Wheal Jane and Wheal Widden.

Old Wheal Jane, West Wheal Jane, Wheal Widden and the Nangiles Mine worked lodes in the footwall of an elvan dyke, which trends in norteastern direction from Mount Wellington Mine across the Carnon valley and can be traced for a distance of about 2 miles to the railway line south of Mount Prickle. In Wheal Jane section, Main lode was opened up by a series of shafts along the strike of the lode (SW779428, Dunstan's Shaft, to SW784430, Gilbert's Shaft) which crosses the road leading from Baldhu to Carnon Downs NE of Treva farm. The coordinates mark the engine house ruin at Giles's Shaft (New Shaft), which also formed part of the sett.

From 1847 to 1895, Wheal Jane produced 3,832 tons of black tin, 740 tons of 4% copper ore, 586 tons of zinc ore, 302 tons of 68% lead ore, 33,340 tons of pyrite, 243 tons of arsenic, 86 tons of arsenopyrite, 100 tons of ochre, 2,921 oz of silver, and 3,666 tons of iron ore from the gossan. From 1906 to 1915, the Falmouth Consolidated group produced 860 tons of black tin and 160 tons of arsenic, mainly from Wheal Jane section. Another 55.5 tons of black tin were raised from Wheal Jane section between 1916 and 1919. In 1983 and 1984, Wheal Jane produced 285,246 tons and 295,093 tons of tin ore, respectively, grading at about 0.6% of tin.

Mineral List

38 valid minerals. 1 (TL) - type locality of valid minerals.

Geochronology

Geologic Time				Rocks, Minerals and Events
Phanerozoic
	Paleozoic
		Permian
			Guadalupian	ⓘ Major polymetallic mineralization ~270 Ma Cornwall, England, UK
			Cisuralian	ⓘ Porphyry dikes intruded (latest age) ~275 Ma Cornwall, England, UK ⓘ Greisenization (latest age) ~280 Ma Cornwall, England, UK ⓘ Porphyry dikes intruded (earliest age) ~280 Ma Cornwall, England, UK ⓘ Formation of metallized pegmatites ~285 Ma Cornwall, England, UK ⓘ Greisenization (earliest age) ~285 Ma Cornwall, England, UK ⓘ Emplacement of major plutons ~295 Ma Cornwall, England, UK

Regional Geology

This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.

Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org

Late Devonian 358.9 - 382.7 Ma ID: 2033495

Upper Devonian Rocks (Undifferentiated) Age: Late Devonian (358.9 - 382.7 Ma) Lithology: Mudstone, siltstone and sandstone Reference: British Geological Survey. DiGMapGB-625. British Geological Survey ©NERC. [23]

Data and map coding provided by Macrostrat.org, used under Creative Commons Attribution 4.0 License

References

External Links