The Tamar Smelting Works at Weirquay, in the parish of Bere Ferrers, Devon, is a surviving silver-lead smelter (1836, Tamar Smelting Company) at Weir Quay. Adjoining the eastern end of the smelter site is the Union Tin Smelter.
This lead/silver smelter is on the Devon bank of the River Tamar, three kilometres north-west of Bere Ferrers parish church.The smelter perimeter wall has a frontage of 300 metres on the Gullytown road, broken by an entry into the eastern portion of the site now used as a house - Fern Cottage - and a west facing frontage of 100 metres on the Hole's Hole road. The west frontage is formed by the former offices - now a house called Treyard - and the main entrance gates into the smelter yard. There is a very full history on the Weir Quay Smelter by Dr Peter Claughton, from where most of this information is obtained.
1835 the Mine at South Hooe was acquired by the Tamar Silver Lead Company. Ore was smelted at the neighbouring property now known as Treyard
1839 was in the hands of Benjamin Somers, a lead smelter from Mendip.
1840s the Union Smelter had been established on a site immediately to the east of the Tamar smelter, but this was treating tin ores and was initially operated as a separate concern.
1845 the smelting works were acquired by Percival Norton Johnson, a Fellow of the Royal Society, the owner of South Hooe mine and the founder of Johnson Matthey and Co. The 18 furnaces could smelt well over 300 tons of lead ore a month and employed between 80 and 90 men. The deep-water berth at Weir Quay was improved to take vessels up to 400 tons and ore was imported for smelting from Spain,France, Newfoundland and Wales.
1850s the smelter employed at least four Cornish flowing (reverberatory) furnaces - two to three in work day and night at any one time - which required the ore to be calcined prior to smelting. At least six calcining furnaces were used in preparing the ore for smelting. Once smelted the silver-rich (fertile) lead was, prior to 1850, refined in cupellation hearths. There it was heated in a blast of air, converting the lead to litharge (lead oxide) which reacted with and absorbed other minor base metallic components. The litharge was drawn off, leaving metallic silver in the hearth, and then re-smelted to produce de-silvered (sterile) lead.
1849-50, on the recommendation of Johnson but against the wishes of a strong minority of shareholders who felt that the capital expenditure to be excessive, the Pattinson De-silvering Process was introduced at the smelter. This process utilised the fact that lead crystalises at a higher temperature than silver - by slowly lowering the temperature of a large pot of molten fertile lead to the point where the lead started to separate out as crystals and skimming them off, an enriched silver-lead was produced. The process was repeated a number of times in a series of pots until the lead content was reduced to a minimum and the residue was then subject to cupellation to produce pure silver.
The cupellation hearth, required a forced draught produced by bellows powered by steam engines, although a water wheel may have been used in the early years of the smelter - the draught for the reverberatory furnaces, including the calciners, was induced through the use of a tall chimney.
1852 it was sold to the British and Colonial Smelting and Reduction Company, of which Johnson was a director, to be operated in conjunction with works at Millwall in London. This company continued to treat silver-rich lead ores, buying from the Tamar mines and elsewhere (including some Australian and South American ores) - operating a total of 20 furnaces and claiming to provide employment to 130 men and boys.
1855 it was decided to wind up the company as losses were mounting. Some dismantling of the furnaces took place on closure, probable to recover silver from the furnace bottoms - part of deficit of 20,000ozs between the assay of ores purchased and silver produced. The site was idle until..
1864/5 a new company - the Tamar Lead and Silver Smelting Co. Ltd. - was advertised to reopen both the Tamar and Union works. The Tamar Lead and Silver Smelting Co. Ltd. was never registered as a limited company and it is unclear what work was carried out on the site after 1865. Some smelting activity may have been returned to the site and it is apparent that the two smelters, Tamar and Union, were considered as one unit after 1865 - the 25" OS map (1st edn.) of 1884 marks both under the name 'Tamar Smelting Works (Tin & Lead, disused)'.
The Union Works was subsequently used as a jam factory and the Tamar works converted to dwellings.
1991, a report for English Heritage states 'The two smelting works (Tamar with Union) at Weirquay are also of considerable national importance, since these sites plus Snailbeach New Cupola (Shropshire) are the three best survivals of reverberatory smelters in England, and the survival of the complete outline of the two adjacent complexes is unique.'