At 19:14 31/01/06, you wrote:
> I read that soft lead was best
>suited for de-silvering.
Ian,
'Soft lead' might be a product of the de-silvering (refining or
cupellation) process - having been recovered from the litharge (lead
oxide) generated by that process. Contamination of metallic lead,
including a significant amount of silver, would make the lead hard /
brittle and not best suited for plumbing and fabrication. So the
'soft lead' from Wensleydale would be low in contaminants and would
not be argentiferous.
Peter
>Would the quality of the lead suit the separation of Silver in medieval
>times?
>
>Some reports around 1800 say that ore from Beldon and Virgin mines (near
>Carperby in Wensleydale, not the other Beldon)produced remarkably soft
>lead. One for Beldon is as follows;-
> 'A partnership at Beldon are getting a considerable quantity of small
>grey and blue ore, I saw one of the smelters a few days ago who says they
>have smelted about 50 pieces and that it runs better & makes more lead
>than was expected from the appearance'
>
>I wonder if Bobscar Vein might have also produced such soft lead near the
>surface.
>
>Some reports suggest that some of the ore in Wensleydale was relatively
>rich in Silver. The Mining Journal says that at one time Keld Heads lead
>produced 13 oz per ton and W. Horn 1906 said that lead from Aysgarth mine
>was also had a high Silver content.
>
>Thanks
>Ian Spensley
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Dr Peter Claughton,
Blaenpant Morfil, nr. Rosebush, Clynderwen, Pembrokeshire, Wales SA66 7RE.
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School of Historical, Political and Sociological Studies (Centre for
South Western Historical Studies)
University of Exeter
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