Gravel Hill Mine

Overview

An iron mine in the cliffs at the north end of Perran Sands, where the Great Perran Iron Lode, one of the largest lodes in south-west England, meets the sea. Worked from the 1720s and last in 1874-82, when the Cornwall Minerals Railway ran a branch to it, it is known to mineralogists for its rare iron phosphates.

History

Gravel Hill Mine worked the western end of the Great Perran Iron Lode where it outcrops in the cliffs at the north-east corner of Perran Sands, about 3.5 km north of Perranporth. The lode, one of the largest in south-west England, runs north-west to south-east for 5 km or more and is up to 30 metres wide, unusually for Cornwall at almost right angles to the tin and copper lodes; at Gravel Hill it splits into a north branch and a south branch separated by killas, and is proven to 60 fathoms. Known first as Penhale Iron Mine, or Cliff Iron Mine, it was at work before 1728 by one account (from 1724 by another), though the Geological Conservation Review dates Penhale Iron Mine's operations from about 1840; it worked again in the 1840s. The lode was developed by a beach adit and cliff-top shafts, among them Borlase's (60 fathoms) and Shepherd's, and inland by a small, deep opencast, the Big Iron Pit, about 155 metres to the south-east. By the 1860s an 11.5-inch puffer engine worked an incline down to the main entrance, and ore was taken to the Gannel for shipment. In 1872 the mine belonged to the Cornish Consolidated Iron Mines Corporation, and from 1874 to 1888 it was the terminus of the Cornwall Minerals Railway's branch from Shepherd's; it passed to the Great Perran Iron Ore and Iron Company in 1877 and to the New Perran Mineral Company by 1878. Output is recorded only for 1874-82: about 7,400 tons of brown haematite at 47 per cent iron, 300 tons of limonite and spathic ore by the Geological Conservation Review's figure (10,379 tons by Mindat's), and 30 to 40 tons of zinc ore; 165 tons of brown iron ore returned as Perran Bay in 1866 may also have come from the cliff workings, and more than 35,000 tons of spathic ore are said to have been raised over the mine's life. The gossany head deposit below the opencast is known for rare iron phosphate minerals, and the mine is the type locality of ferroberaunite. Below adit level, where the oxidised zone ends, the lode narrows to blue clay, or fluccan, with fragments of sulphides. The mine was reopened around 1916 but apparently raised no ore.

Geology

The north-west end of the Perran Iron Lode, a brecciated fault-hosted lode in Lower Devonian Meadfoot Group slates (killas): siderite with black sphalerite, oxidised near surface to haematite, goethite and limonite to about 60 m, cut by later north-south cross-courses with argentiferous galena. At Gravel Hill it is split into a north branch (about 4 m) and a south branch (about 12 m).

Geological setting: Faults and Fractures (well documented example), Veins and Lodes (well documented example)

Workings

A beach adit and cliff-top shafts, including Borlase's (60 fathoms) and Shepherd's, with open stoping of the lode in the cliff and a small, deep opencast, the Big Iron Pit, about 155 metres inland. An 11.5-inch puffer engine worked an incline to the main entrance in the 1860s, and there were at least two engine houses. Both branches of the lode were stoped from the cliff face, leaving large caverns; the beach adit follows the north branch.

Closure

Output is recorded until 1882, and the mine was probably abandoned then; the railway branch that served it was used until 1888. By 1892 most of the Perran iron mines had stopped because of the low price of iron. The mine was reopened around 1916 but apparently produced no ore.

What remains

Scant remains survive in the cliff at the north end of Perran Beach; the cliff workings are partly flooded and drain copious mine water, and by 2004 little remained of either engine house. The site is a Geological Conservation Review site for its mineralisation.

The cliff opencast, adit entrances at beach level, the line of the incline and slight remains of an engine house; the railway line is roughly followed by the road through the dunes.

Related mines

• Penhale and Wheal Golden — Both at the north end of Perran Sands; Penhale also worked the Perran Iron Lode, which Gravel Hill worked.
• Treamble Mine — Both worked the Perran Iron Lode; the Gravel Hill tramway joined the Treamble branch at its terminus.

What's uncertain

Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.

• Originally known as Penhale Iron Mine, Gravel Hill is known to have been at work before 1728, also in the 1840s, and from 1874-82. (disputed) ¹
• Gravel Hill Mine was first known as Penhale Iron Mine, with operations commencing about 1840. (disputed) ²
• The last working produced about 8,000 tons of iron ore and 30 tons of zinc ore, and more than 35,000 tons of spathose ore were raised during the mine's life. (disputed) ¹
• Between 1874 and 1882 Gravel Hill produced 7,400 tons of brown iron ore at 47% iron, 10,379 tons of mixed limonite and spathic ores and 30 tons of zinc ore at 40%; 165 tons of brown iron ore returned in 1866 as Perran Bay may refer to the cliff workings. (disputed) ⁶

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• Originally known as Penhale Iron Mine, Gravel Hill is known to have been at work before 1728, also in the 1840s, and from 1874-82. (disputed) ¹
• Gravel Hill Mine was first known as Penhale Iron Mine, with operations commencing about 1840. (disputed) ²
• In 1872 the mine belonged to the Cornish Consolidated Iron Mines Corporation and was reached by the Cornwall Minerals Railway's Shepherd's to Gravel Hill branch, built in 1874 and used until 1888; from 1877 it was owned by the Great Perran Iron Ore and Iron Company and by 1878 by the New Perran Mineral Company. ³
• Output in 1874-82 was 7,400 tons of brown haematite, 300 tons of mixed limonite and 30 tons of zinc ore. ²
• The last working produced about 8,000 tons of iron ore and 30 tons of zinc ore, and more than 35,000 tons of spathose ore were raised during the mine's life. (disputed) ¹
• The lode is proven to 60 fathoms and split into a North Branch and a South Branch separated by a 'horse' of killas; it was developed by a beach adit and cliff-top shafts and worked 155 metres inland in the Big Iron Pit. ^1,2
• The Perran Iron Lode strikes WNW-ESE for almost 5 km from the coast at Gravel Hill, dips south-west and is up to 20 m wide; its siderite is altered by supergene activity to limonite and haematite to depths of up to 70 m. ⁴
• The head deposit below the opencast contains rare iron phosphates including rockbridgeite, strengite, strunzite and beraunite; the mine is the type locality of ferroberaunite. ^2,5
• Both branches of the lode were worked from the cliff face and their stopes still stand as large caverns; underground development was from a beach-level adit following the north branch and from shafts near the cliff edge, and an excavation just north of the caverns is an old quarry in an elvan dyke, unrelated to the mine. ⁶
• The base of the oxidised zone is about at adit level; below it the lode is reported to be narrow and to consist mainly of blue fluccan (clay) with fragments of sulphides. Midway between the cliff and the Big Iron Pit it is crossed by a north-south lode believed to be the southern extension of the Phoenix Mine lode. ⁶
• Between 1874 and 1882 Gravel Hill produced 7,400 tons of brown iron ore at 47% iron, 10,379 tons of mixed limonite and spathic ores and 30 tons of zinc ore at 40%; 165 tons of brown iron ore returned in 1866 as Perran Bay may refer to the cliff workings. (disputed) ⁶
• The mine was reopened around 1916 but apparently produced no ore. ⁶
• Gravel Hill Mine is the type locality of ferroberaunite, among 31 valid minerals recorded there. ⁶

Photographs & further reading

Sources

1. (secondary) Gravel Hill Mine, Cornwall — Cornwall Calling
2. (secondary) Gravel Hill Mine, Cornwall (Geological Conservation Review, Mineralization of England and Wales, GCR vol. 36) — JNCC / Scottish Geology Trust GeoGuide
3. (secondary) Gravel Hill Mine — Explore Cornwall
4. (secondary) Perran Iron Lode, Cornwall — Cornwall Calling
5. (observational) Gravel Hill Mine, Perran Iron Lode, Perranzabuloe, Cornwall — Albion Fire and Ice
6. (secondary) Gravel Hill Mine (Cliff Iron Mine; Penhale Iron Mine), Perran Iron Lode, Perranzabuloe, Cornwall — mindat.org

Record created: 18 September 2026 · Last researched: 19 September 2026