The copper industry was the prime mover to the Industrial explosion that occurred in and around the Llanelli area in the early 19th century. With docks being added and collieries such as the Box, Penprys and Old Castle being sunk to name but a few.
Another industry allied to copper was the smelting of Lead and recovery of Silver this took place on the site of the original Cambrian Copper Works adjacent to the Carmarthenshire Docks and shipbuilding yard. Mills were also erected for the rolling of copper and brass.
A number of different processes were used for the extraction of silver from the copper and lead:-
Cupellation, this involved allowing a mixture of silver and lead to be melted in a cupel (a flat, porous dish made of a refractory or high-temperature-resistant material such as crushed animal bones). A blast of hot air was directed onto the mixture in a special furnace. The impurities then oxidised and partly vaporised and were also absorbed into the pores of the cupel. This process was repeated over and over again until only pure silver remained. Gold and silver is assayed using this type of process and is known as “Fire Assaying”.
Eliquation, this involved smelting a mixture of lead and enriched copper. This alloy was then cast into small “tablets.” These were then heated slowly and because of the different melting points of copper and lead, the lead containing nearly all of the silver would run off first leaving a soft mass of copper.
Pattinsoning, this process was named after Pattinson the man who invented it. A large quantity of molten lead containing a small quantity of silver was allowed to cool very slowly until the lead began to solidify. At this point pure lead crystals began to form on the top of the molten metal, these were then scooped off the top with ladles. The metal remaining became richer and richer in silver as the process was repeated.
John Innes in his book “Old Llanelly” writes that “as much as two million ounces of silver was extracted and refined yearly”, using these methods. This industry seems to have gone into steep decline early in the 1900’s, probably due to competition from America and Germany.
Photograph of the Cambrian Works by kind permission of Llanelli Reference Library