Palmerston Quarry

Overview

The lowest of the three great quarries on the mountain above Blaenau Ffestiniog, worked by the Welsh Slate Company from 1825 and known as the Lower Quarry or Lord Palmerston's Quarry. Its underground workings reached the Ffestiniog Railway by 1838, it opened the first steam-driven cutting mill in the district around 1840, and by the 1870s it was turning out some 50,000 tons of finished slate a year. It destroyed itself: because it lay directly beneath the Middle Quarry and was held up by that quarry's slower progress, the company began robbing the slate from the walls supporting the workings above. The Great Fall of 16 February 1883 brought down 6.25 million tons of rock, and the lawsuit that followed cost the company its lease. Palmerston was absorbed into the amalgamated Oakeley Quarry.

History

Slate quarrying on the mountain above Rhiwbryfdir began in 1818, when the Liverpool merchant Samuel Holland leased land from the Oakeley family of Tan y Bwlch on a three-year lease at a ten per cent royalty. Holland took a further twenty-one-year lease in 1821 and sold it in 1825 to the Welsh Slate Company, which extended the quarry considerably. That undertaking was the lowest on the mountain and became known as the Lower Quarry, or Lord Palmerston's Quarry, the name this record carries. Holland opened a new quarry above it at Cesail, later the Upper Quarry, and in 1842, when the original lease expired, a new lease was granted on condition that both undertakings gave up land for a third quarry between them. That was the Middle Quarry, Gloddfa Ganol, worked by the Rhiwbryfdir Slate Company. From 1840 the easily reached surface slate was exhausted and all three went underground, with complex lease provisions written specifically to keep their workings from conflicting. Palmerston was the technical leader of the three in its early years. Its extensive underground workings were connected to the Ffestiniog Railway by 1838, and around 1840 it opened the first steam-driven cutting mill in the district. By the 1870s it was producing about 50,000 tons of finished slate a year, and production and profits at all three quarries peaked in that decade. The trouble was structural and it was of the company's own making. The Lower Quarry's mine ran directly beneath the Middle Quarry's, and because both were working the same vein of slate, Palmerston's progress was limited by how fast Gloddfa Ganol advanced above it. Gloddfa Ganol mined more slowly than the Welsh Slate Company wanted, so the company took the dangerous decision to remove slate from the walls supporting the workings above. Through the 1870s underground rockfalls became an increasing worry. On 6 December 1882 a major fall forced the company to shut down all operations, and on 16 February 1883 came the Great Fall, 6.25 million tons of rock in a single event, severely damaging the workings. The leases for the Upper and Middle quarries had expired in 1878 and W. E. Oakeley had consolidated those two into the Oakeley quarry, but the Welsh Slate Company had negotiated an extension in advance and went on working the Lower Quarry separately. The Great Fall ended that. It triggered a lawsuit between the Oakeley company and the Welsh Slate Company which the latter lost, and being unable to pay the resulting fine it gave up its lease. All three quarries were amalgamated into a single operation as the Oakeley Quarry, which closed in 1971.

Geology

Palmerston worked the Cambrian slate belt of Blaenau Ffestiniog, where the beds dip so that a single vein of slate can be reached at different heights on the mountain by different quarries. That is the fact that governs this quarry's whole history: the Lower Quarry and the Middle Quarry above it were working the same vein, one directly under the other. By 1840 the slate that could be won by surface quarrying with the methods of the day was exhausted and all the workings went underground, into chambers separated by pillars and walls of slate left in place to hold the roof. Removing those supports is what caused the falls of 1882 and 1883.

Geological setting: Slate and Regional Metamorphism (well documented example)

Workings

Extensive underground chambers, connected to the Ffestiniog Railway by 1838, which is early for the district. Around 1840 the quarry opened the first steam-driven cutting mill in Blaenau Ffestiniog. Working was by chamber and pillar, with walls of slate left to support the ground above; the Welsh Slate Company's decision to take slate out of those supporting walls, in order to get ahead of the Middle Quarry that was limiting its progress, is described in the sources as literally undermining the workings above. Complex provisions had been written into the leases from 1842 precisely to stop the three quarries' underground workings from conflicting, and they failed.

Closure

Palmerston did not close in the ordinary way. A major rockfall on 6 December 1882 forced the Welsh Slate Company to shut down all operations, instability continued, and the Great Fall of 16 February 1883 brought down 6.25 million tons of rock and severely damaged the workings. The Oakeley company sued, the Welsh Slate Company lost, and unable to pay the fine it surrendered its lease. The quarry was amalgamated with the Upper and Middle quarries into the single Oakeley operation, which itself closed in 1971. The two accounts read differ slightly in emphasis, one saying Oakeley took ownership after suing and the other that the Welsh Slate Company gave up its lease when it could not pay; they are compatible and both are given here.

What remains

Nothing survives as a separate Palmerston site. The ground was absorbed into the Oakeley quarry after 1883 and worked as part of it until 1971, and it lies within the wider Rhiwbryfdir complex above Blaenau Ffestiniog. No description specific to the Palmerston workings as they stand today was found in the sources read.

Not separately identifiable. What is on the ground belongs to the amalgamated Oakeley quarry, whose own record covers it.

Related mines

• Gloddfa Ganol Quarry — The two quarries worked the same vein of slate directly above and below one another, Palmerston beneath Gloddfa Ganol. Palmerston's progress was limited by the Middle Quarry's slower advance, and the Welsh Slate Company's removal of the slate walls supporting the workings above is what undermined Gloddfa Ganol and caused the falls of 1882 and 1883.
• Oakeley Quarry — Palmerston, the Lower Quarry, was amalgamated into Oakeley after the Great Fall of 16 February 1883 and the lawsuit the Welsh Slate Company lost, and was worked as part of the single Oakeley operation thereafter.

Nearby mines

• Cwmorthin Slate Mine — 1.1 km SW
• Oakeley Quarry — 1.4 km E
• Wrysgan Quarry — 1.6 km SW
• Nyth-y-Gigfran Quarry — 2.0 km S
• Votty and Bowydd Quarry — 2.1 km E

Straight-line distance, within 15 km. Show on the map.

Recorded claims

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

• Samuel Holland leased land near Rhiwbryfdir farm from the Oakeley family in 1818 and sold his twenty-one-year lease in 1825 to the Welsh Slate Company, whose undertaking was the lowest on the mountain and became known as the Lower Quarry, also called Lord Palmerston's Quarry. ¹
• The quarry's extensive underground workings were connected to the Ffestiniog Railway by 1838 and it opened the first steam-driven cutting mill in the district around 1840. By the 1870s annual production was around 50,000 tons of finished slate. ²
• The Lower Quarry's mine extended directly beneath that of the Middle Quarry and both worked the same vein, so its progress was limited by how fast the Middle Quarry advanced. The Welsh Slate Company took the dangerous decision to remove slate from the walls supporting the workings above, undermining them, and through the 1870s underground rockfalls became an increasing concern. ¹
• A major rockfall on 6 December 1882 forced all operations to shut down, and on 16 February 1883 the Great Fall brought down 6.25 million tons of rock in a single event, severely damaging the workings. ¹
• The fall triggered a lawsuit between the Oakeley company and the Welsh Slate Company which the latter lost; unable to pay the fine, it gave up its lease and the three quarries were amalgamated into the single Oakeley operation. ¹
• Festipedia's account has Oakeley suing the owners of the Lord Palmerston Quarry and taking ownership of it, after a number of underground collapses culminating in the falls of 1882 and 1883 threatened to destabilise the two Oakeley-owned quarries above. ²

Photographs & further reading

Sources

1. (secondary) Oakeley quarry — Wikipedia
2. (secondary) Oakeley Slate Quarries — Festipedia

Record created: 10 September 2026 · Last researched: 10 September 2026