Llanelli Naturalists Newsletter - May 1995 - No 1
RH Davies

During the nineteenth century, virtually all of Britain's copper was smelted along the coasts adjoining the western end of the South Wales coalfield - an area extending from Neath to Burry Port. The location of this industry was determined by the abundance of local coals, which were ideal for smelting, in a position midway between the Cornish mines and the factories of the English Midlands, (Rees 1993). The copper industry was established in Llanelli by Daniel & Co in 1805. This concern was energetically developed by R J Nevill of Llangennech Park.

Whilst copper smelting brought prosperity to these areas, there was an environmental cost. Copper ores are impure and many roastings and meltings were required to extract the metal. This process produced enormous volumes of smoke containing sulphur and arsenic as well as large quantities of slag.

Charles Cliffe gave a graphic description of a landscape created by the copper industry in 1848.

"The Swansea Valley forms no bad representation of the infernal regions, for the smell aids the eye. Large groups of odd chimneys and rackety flues emit sulphurous arsenical smoke or flame. All the vegetation is blasted in the valley and adjoining hills".

The simplest method of solving the smoke problem was to build tall stacks. In 1839, the Llanelli Copper Company erected a stack 272 feet high. Another was built in 1860 which was 320 feet high, this was known as "Y Stac Fawr" (the big stack) and was the tallest chimney in Britain for some years. These stacks undoubtedly removed much of the local fallout but only to disperse it down wind.

It is ironic that in 1864, soon after the completion of the Stac Fawr, the Llanelli Local Board of Health had to obtain a chemical analysis of crops from the town estate lands on Morfa Mawr (the Machynys - Trostre area). The source of this pollution was identified as a chemical works which refined arsenic and manufactures sulphuric acid. It was established that furnace fumes mixed with the fumes of concentrated sulphuric acid to form a toxic cocktail. This phenomenon was exacerbated during damp weather (Herepath 1864).

There can be little doubt that the copper industry adversely affected the local lichen flora. Whilst it is impossible to quantify the sulphur burdens of the time, it is reasonable to assume that this initiated the creation of a local lichen desert. The atmospheric pollution produced by the Steel and Tinplate industries would have added significantly to this in later years.

The almost total absence of corticolous lichens from Stradey Woods (SN485015) and Troserch Woods (SN550040) testify to this. There is also an impoverished saxicolous lichen flora within the Llanelli urban area.

The injurious effects of copper pollution were not widely accepted. It was argued that the smoke acted as a shield against cholera and malaria. A strange piece of local folklore relates how Llanelli was spared from the ravages of the Potato Blight. It was believed that the fallout from the stacks protected the potato plants and this was by no means impossible as the first fungicide to be developed contained copper. This was "Bordeaux Mixture", a solution of copper sulphate and lime which was devised by Millardet in the 1880's as a control for mildews on grapevines.

Belief in the health enhancing properties of smoke continued into the twentieth century. J.D. Innes, a local writer observed: -

"This writer is convinced that these fumes are disinfectant and salutary, although ignorant people have a prejudice against them"

Apart from the gaseous emissions, copper smelting produced large amounts of slag as a waste produce. The Llanelli copperworks was situated on low ground near the sea and so much of the slag was tipped nearby so as to allow more land to be reclaimed from the sea. Much of this land was later to become industrial sites eg the Welsh Metal Stamping Works, and it was this enamelware factory that gave Llanelli its nickname "Sosban". Considerable amounts of slag were used to construct a breakwater and other works in the Burry Inlet.

This slag contained significant amounts of copper. Pieces of slag which are exposed to the tides show striking green colours. This material was exported to Belgium in the years after the Second World War for reprocessing eg the "S.S. Holdernore" sailed from Llanelli to Antwerp with 970 tons of slag in August 1948 (Craig 1991).

During the nineteenth century, slag was marketed as a specialised building material. Copper slag was cast into square, angular and half round block and were used as wall coping stones. They were manufactured from Cornish ores and were noted for their permanence and their frost resistant properties (Innes 1902).

Many of these walls with slag coping stones have been demolished during the last 150 years. It is fortunate that at least two such walls survive and can be dated fairly accurately. The period during which the copperworks operated coincided with the development of our railway system. Several hundred metres of wall survive alongside the Heart of Wales line near Llangennech. This low wall runs alongside the Llwchwr estuary and was built by the  Llanelli Railway & Dock Co. in 1837. Another slag coped wall runs along the seaward side of the Llanelli - Carmarthen line between St Ishmael and Ferryside. This was constructed by the South Wales Railway in 1851.

During visits in 1991, it was noted that these slag copings had a well established lichen flora. Species identified included:

  • Candelariella vitellina Parmelia glabratula Physcia caesia
  • Physcia adscendens Verrucaria maura
  • Xanthoria parietina

Whilst these species show high to moderate resistance to sulphur dioxide pollution, they must also posses a resistance to heavy metals. The St. Ishmael site is in an area of low atmospheric pollution. This is confirmed by the presence of Ramalina fastigiata and Ramalina fraxinea on ash branches nearby.

The lichens growing on these copings have developed in approximately 150 years. They have exploited an unpromising artificial habitat. The utilisation of a copper rich substrate appears unusual, bearing in mind the known sensitivity of fungi to this metal.

Survey work has been carried out recently on lichens growing on heavy metal wastes at various mid-Wales mine sites. This was done because such sites are disappearing rapidly because of landscaping schemes.

The Llanelli area is undergoing similar rapid change as former industrial landscapes are replaced. A case needs to be made so that examples of a vernacular building material are preserved and that their lichen communities are studied.


Craig, R. (1991). Uses of Copper Slag. South West Wales Industrial Archaeology Society Bulletin: 55

Herapath, J. (1864). Report to the Llanelli Local Board of Health, July 1864. Llanelli Public Library: LC3814.

Innes, J.D. (1902). Old Llanelli. Western Mail, Cardiff.

Rees, R. (1993). The Great Copper Trials. History Today.. 43.