|Latitude & Longitude (WGS84):||50° 24' 23'' North , 4° 38' 30'' West|
|Latitude & Longitude (decimal):||50.40639,-4.64167|
|UK National Grid Reference:||SX123597|
|Other regions containing this locality:||St Austell Mining District, Cornwall, England, UK|
Devon and Cornwall metalliferous mining district, England, UK
|Köppen climate type:||Cfb : Temperate oceanic climate|
Wheal Fortescue was first opened in 1855, when at a shallow depth muriate of silver (chlorargyrite) was found. At a depth of ony 3 fathoms the lode split, and the mine stoped in 1857. (Beacon Hill mine, may have been a local name)
In 1860 the mine reopened under the name of Silver Vein, when the mine was developed to a 50 fathom level. There was some small development on an east-west copper lode.
The silver occurred in the north-south lode. Probably in common with other such silver deposits in Cornwall, it may have been at the intersection of the two lodes.
Recorded output is scant:
3.5 tons of lead ore.
40 oz of silver (from lead ore)
61.25 tons of silver ore.
13 valid minerals.
|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
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
|Lower Devonian Rocks (Undifferentiated)|
393.3 - 419.2 Ma
|Early Devonian sandstone|