Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat Articles
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsThe ElementsUsersBooks & MagazinesMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Ystrad Mine (Silurian Mine), Betws Garmon, Gwynedd, Wales, UK

This page is currently not sponsored. Click here to sponsor this page.
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.

Mineral List

3 valid minerals.

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

456.5 - 470 Ma
Llanvirn Rocks (Undifferentiated)

Age: Ordovician (456.5 - 470 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

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2019, except where stated. Most political location boundaries are © OpenStreetMap contributors. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: June 20, 2019 06:08:39 Page generated: October 6, 2017 14:16:23
Go to top of page