Stenna Gwyn Mine (Stennagwyn Mine), Foxhole, St Stephen-in-Brannel, St Austell District, Cornwall, England, UK
|Latitude & Longitude (WGS84):||50° 21' 41'' North , 4° 51' 56'' West|
|Latitude & Longitude (decimal):||50.36139,-4.86556|
|UK National Grid Reference:||SW962553|
|Other regions containing this locality:||Devon and Cornwall metalliferous mining district, England, UK|
|Köppen climate type:||Cfb : Temperate oceanic climate|
An ancient underground mine which ceased work shortly after 1804. An attempt may have been made to re-open it in 1880 when a return of 1 ton of black tin is recorded. Online court records show a dispute over unpaid bills for this period.
Stennagwyn is referred to under a number of different spellings including Stannagwyn and Stenna Gwinn which was used repeatedly by William Gregor in his correspondence regarding his research on Wavellite and Fluellite.
When working, Stennagwyn had china clay works immediately to the north and south. North of the mine, the works eventually became the West of England China Clay Works which has been cleared and the site is now occupied by the currently active Goverseth Plant. Immediately to the south was the North Carloggas China Clay works. The china clay works in the close vicinity of Stennagwyn were amongst the first to supply materials to the fledgling potteries in Stoke on Trent.
In the early 1980's there were at least two remaining chimneys from Stennagwyn Mine together with the foundations of a building. The chimney immediately behind the terrace of cottages had the base of a small building nearby. Unfortunately, since then, the area has been levelled to provide a football pitch, clubhouse, day center for young children and a static caravan park. Everything behind the terrace has either been flattened or pushed into a single heap. The one remaining collapsed chimney is the only feature listed by Herring & Smith (1991). Even the name Stennagwyn has been removed from some modern maps although the farmhouse immediately to the south of the mine site still keeps the name.
With so much happening in this relatively small area, it is impossible to find any original features in situ. The 24-inch map of 1908 shows extensive dumps that are now all lost.
Beer (1988) reports that the mine was worked from two shafts, adit level and a large openwork. None of this can be found today. One of the pipes going under the railway may take water from an adit? Industrial archaeological features can be viewed from the railway line. The locals have forced a footpath across the site, including the seldom used railway track, to link Goonamaris with the convenience store in Foxhole.
Carpholite supposedly collected here in 1952 by Arthur Kingsbury (1906-68) is now considered unlikely. This is one of a number of likely or definitely falsified Kingsbury localities.
17 valid minerals. 1 (TL) - type locality of valid minerals. 2 erroneous literature entries.
Rock Types Recorded
Select Rock List TypeAlphabetical List Tree Diagram
Entries shown in red are rocks recorded for this region.
|Geologic Time||Rocks, Minerals and Events|
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
|Permian - Carboniferous|
252.17 - 358.9 Ma
|Unnamed Igneous Intrusion, Carboniferous To Permian|
Age: Paleozoic (252.17 - 358.9 Ma)
Reference: British Geological Survey. DiGMapGB-625. British Geological Survey ©NERC. 
323.2 - 358.9 Ma
|Paleozoic sedimentary rocks|
Age: Mississippian (323.2 - 358.9 Ma)
Lithology: Sedimentary rocks
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
393.3 - 419.2 Ma
|Early Devonian sandstone|