Lead mining in the Peak District (4th edition)

T.D. Ford & J.H. Rieuwerts (2000) Landmark Publishing

Introduction: Geology

The common ores mined in the Peak District are GALENA (lead sulphide), SPHALERITE (zinc sulphide), FLUORITE (calcium fluoride), BARYTE (barium sulphate) and CALCITE (calcium carbonate).

RAKES are major veins formed in vertical fissures often 2-3 m wide but up to 15 m wide. They can be 4-5 km long and some have been mined to 200 m deep.

SCRINS are smaller versions of rakes not often more than 50 cm across and 1 km long.

FLATS are horizontal deposits laying parallel to the bedding.

PIPES are irregular deposits parallel to the bedding.

Pipes and flats are often close to or capped by thin volcanic deposits know as wayboards.

The mineral deposits were formed from hot fluids which came from 2-3 km below the surface and picked up minerals on the way. These were precipitated by cooling, mixing with cooler surface waters, reaction with sulphur compounds in pore waters or reaction with oxygen in such waters. This reached a climax at the end of the Carboniferous 270 million years ago.

Galena (PbS) is easily recognised by its silvery metallic lustre. Veins contained form as much as 10% to as little as 2%. The veins along the eastern margin of the mineral field also contained sphalerite (ZnS) recognised by its dark brown chocolate colour and also known as blende or blackjack. It had little value until brass (an alloy of zinc and copper) became popular in Victorian times. In a few areas the sulphides have been oxidised to carbonates, cerussite (lead carbonate) and smithsonite (zinc carbonate, commonly known as calamine). Cerussite is the raw material for white lead and several White Rakes are allegedly named after it. The gangue minerals of metal extraction were fluorspar, barytes and calcite. Nowadays these are the main products and metallic ores are byproducts. Fluorspar (CaF) is the chief source of fluorine for the chemical industry. It is largely confined to a 2 km wide strip at the eastern margin of the ore field. Baryte (BaSO4) and calcite (CaCO3) complete the 5 minerals which form the bulk of the mining activity in the Peak District.

This is followed by a comprehensive history of mining in the Peak District and then a list of itineries.

Itineraries:

1. Castleton

2. Peak Forest

3. Hucklow, Eyam, & Stoney Middleton Area

4. Sheldon & the Magpie Mine

5. The Ashford Black Marble Mines & Mill

6. The Lathkill Dale Mines

7. Hillocks & Knotlow Mines, Monyash

8. The Alport Mines

9. The Lead Mining Village of Winster

10. The Wensley-Darley Area & Mill Close Mine

11. The Matlock Area

12. Cromford & Bole Hill

13. Good Luck Mine, Middleton-By-Wirksworth

14. Wirksworth

15. Carsington Pasture & Brassington

16. The Crich Area

17. Stonedge Cupola, Ashover

18. The Ecton Copper Mines

 

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