Eight members met at the Foregill Gate Watersplash for a visit to the lead bale sites on Calver Hill. The walk was organised by Sallie Bassham and led by Richard Smith and was based on the paper: Smith R. and Murphy S., 2003, ‘Bale smelting sites at Calver Hill, Swaledale, Yorkshire’, British Mining, 73, pp. 46-71. The various sites were characterised by the presence of lead smelting debris such as slag, lead prills, partially smelted galena, glazed stones and to a lesser extent reddened stone. The technology used has been assumed to be bale smelting and pre-17th century but more work is needed on this aspect.
The first sites we visited were barren patches of stone with occasional splashes of cream/yellow lead silicate slag. One site (NZ 00306 00388) was cut through by a later limestone quarry with the remains of a collapsed kiln and traces of coal which no doubt came from this later operation. Lead silicate melts at around 760 oC and the evidence was indicative of a low-temperature smelt with well-dressed ore as there were few signs of smelted gangue. These sites were fairly close to shallow excavations and it was conjectured that smelting had probably been carried out by the miners.
This is just the first part of the report, the full report can be found in the November 2016 newsletter.