Ystrad Mine (Silurian Mine), Betws Garmon, Gwynedd, Wales, UK
|Latitude & Longitude (WGS84):||53° 5' 36'' North , 4° 10' 50'' West|
|Latitude & Longitude (decimal):||53.093512325, -4.18059060754|
|UK National Grid Reference:||SH540574|
|Other/historical region names associated with this locality:||Caernarvonshire|
|Other regions containing this locality:||Snowdonia National Park, Wales, UK|
The largest of the Gwynedd iron mines, all of which exploited sedimentary deposits precipitated as nodules within a cleaved mudstone, the Nant Ffrancon formation, that occurs widely across this area of north Wales.
The workings, variously known as Ystrad Mine or Silurian Mine run in a series of 8 large chambers in long gash for about 700 yards up the hillside of Moel Eilio at Betws Garmon ending on the 700ft contour. A smaller adjoining mine, Garregfawr Mine lies on the same vein or bed of ore as does the largely unsuccessful Tyddynbach Mine. A small surface trial, Cwm Buchan Mine, was located on a separate ore body about a mile to the south east of Betws Garmon on the slope of Craig Cwm Buchan.
Although instructions were first issued to sell leases for iron ore mining on the property in 1891, the mine was not worked until 1909. Until about 1912 the initial workings were at surface, thereafter the majority of the workings were underground. Mining peaked in 1917 when 35 men were employed ungerground and 8 men above ground. The mine closed in 1919.
The property leases were controlled by the Betws Garmon Iron Ore Company (1909-12), which evolved into the Phosphoric Iron Ore Company Ltd (1912-13). In 1913 the company was wound up and the lease obtained by the Silurian Iron Ore Company Ltd (1913-19), which also controlled other Caernarvonshire iron mining interests.
Although easily worked, the mine having no water problems and the undergroung workings not requiring timbering, the ore, like all of the Gwynedd iron mines had a high silica content which rendered it unattractive to distant ironmasters and which contributed to the mine's ultimate failure.
The site still shows the remains of an incline and winding houses.
Ref: Caernarvonshire Iron Ore, Jeremy S Wilkinson, British Mining No. 78, Memoirs 2005, Northern Mines Research Society.
3 valid minerals.
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
456.5 - 470 Ma
|Llanvirn Rocks (Undifferentiated)|