Castlecaldwell Feldspar Mine

Overview

A feldspar and kaolin working at Larkhill on the Castlecaldwell estate, discovered by an 1853 mineral survey commissioned to give famine-hit tenants new employment, that directly supplied the raw materials for the Belleek Pottery — still Ireland's best-known ceramics maker — until the last feldspar working closed in the 1940s.

History

John Caldwell Bloomfield inherited the Castlecaldwell estate, on the shore of Lower Lough Erne near Belleek, in 1849. An amateur mineralogist, and looking for ways to give his tenants new work in the aftermath of the Great Famine, he commissioned a geological survey of his lands in 1853. It found workable deposits of feldspar and kaolin (china clay) at Larkhill, a townland around eight miles from Belleek within the wider Castlecaldwell estate — sufficient, Bloomfield judged, to make commercial mining worthwhile. He went into partnership with the London architect Robert Williams Armstrong and the Dublin merchant David McBirney, and the resulting company, David McBirney & Co, built a pottery at Belleek itself, with construction beginning in 1858; Bloomfield also arranged for a railway to reach the village so coal could be brought in to fire the kilns. A crushing mill was built at Belleek on the site of an old corn mill, using waterpower from the River Erne to process the feldspar and kaolin hauled down from Larkhill. Before the Belleek works itself was fully up and running, the mined feldspar and kaolin were also exported to England, supplying a contract with Kerr & Binns of Worcester (the forerunner of Royal Worcester) — an early source of income and an important trade connection for the fledgling business.

The pottery itself went on to become internationally known for a distinctive, iridescent-glazed Parian ware, achieved from 1863 and supplying clients as prominent as Queen Victoria and the Prince of Wales by 1865, and it survives as a working pottery and visitor attraction today. Mining of the raw materials that founded it continued at Larkhill on a much smaller scale for decades afterward, with the last working for feldspar closing in the 1940s; Belleek Pottery has sourced its raw materials from elsewhere ever since.

Geology

The feldspar worked at Larkhill occurs in pegmatite veins intruding metamorphic rocks of the Moinian Lough Derg Group in west County Fermanagh — coarse-grained igneous veins, typical of many British and Irish feldspar and china clay workings, in which slow cooling allowed unusually large crystals of feldspar, quartz and associated kaolinised minerals to form.

Workings

Feldspar and kaolin were dug at Larkhill and hauled roughly eight miles to a purpose-built crushing mill at Belleek itself, sited on an old corn mill and powered by the River Erne, which ground the raw minerals to the fine material needed for pottery glaze and body.

Closure

The last working for feldspar at Larkhill closed in the 1940s; Belleek Pottery, which the mine had originally been developed to supply, has sourced its raw materials elsewhere ever since and continues in production today.

What remains

The wider Castlecaldwell estate is now Castle Caldwell Forest, a roughly 200ha nature reserve of ash, beech, oak and holly woodland on the shore of Lower Lough Erne, with waymarked trails, a jetty and an industrial-scale lime kiln surviving on site as a reminder of the estate's wider mineral-working history; the castle ruin itself has stood empty since the early 20th century.

A lime kiln and other traces of the estate's mineral workings survive within Castle Caldwell Forest; the crushing mill site at Belleek itself has long since been redeveloped as part of the working pottery.

Recorded claims

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

• John Caldwell Bloomfield, having inherited the Castlecaldwell estate in 1849, commissioned a mineral survey in 1853 that identified commercially workable feldspar and kaolin deposits at Larkhill, about eight miles from Belleek. ¹
• Bloomfield partnered with architect Robert Williams Armstrong and merchant David McBirney to found David McBirney & Co, building the Belleek pottery from 1858 and arranging a rail connection so coal could reach the kilns. ^1,2
• Feldspar and kaolin from Larkhill were crushed at a purpose-built mill at Belleek, powered by the River Erne on the site of an old corn mill, and were also exported to supply a contract with Kerr & Binns of Worcester, forerunner of Royal Worcester. ¹
• The feldspar worked at Larkhill occurs in pegmatite veins intruding the Moinian Lough Derg Group in west County Fermanagh. ³
• The last feldspar working at Larkhill closed in the 1940s. ¹

Sources

1. (secondary) Belleek Pottery museum entry — VIPA (Voluntary and Independent Museums Association)
2. (secondary) Belleek Pottery — Wikipedia
3. (primary) Bulk minerals, mineral resources, Northern Ireland — British Geological Survey (Earthwise)

Record created: 26 August 2026 · Last researched: 26 August 2026