At 09:46 01/12/04 +0100, Service Culturel CCSTI wrote:
>This discussion interests us here for our own preoccupations in early
>metallurgy, and we have two questions :
>
>- what are the written sources for these figures and process descriptions,
>and how may one deduce such precise percentages from these documents ;
>
>- have there been any recent experimentation works following archaic
>processes, accompanied by archaeometric protocols (raw material and
>resulting matter analysis)
Ian / Bruno,
On the first question - the data for the description of the process in the
late medieval period comes from the accounts of the English Crown,
particularly detailed during the period of direct working of the mines in
Devon between 1292 and the middle of the 14th century (the bulk of which
are in the Public Record Office, Kew, E101). For the early part of the 14th
century the accounts include figures for the amount of ore raised; the
quantity of 'fertile' lead, ie. lead containing silver, produced; the
amount of silver sent to the exchange in London or, occasionally, sold
direct from the mine; and the amount of 'sterile' lead, ie. metal from
which the silver had been recovered (resmelted litharge), sold. The whole
operation was a state enterprise, with production monitored by regular
assay; returns were made in duplicate, one by the keeper of the mines, the
other by his controller, and verified in the Exchequer, to whom the
officers had to account for any shortfalls. So we have some confidence in
the figures.
As to the second question - I'm not aware of any experimental archaeology
on the process of large scale cupellation but it is a question which might
be addressed to archaeometallurgists in the UK (the Historical Metallurgy
Society) and elswhere through our sister list <[log in to unmask]>
to which I'm copying this message. It would certainly be up for discussion
at the Historical Metallurgy Society conference, at Middleham in Yorkshire
9-11 September 2005, when the subject will be the Mining and Metallurgy of
Lead and Silver. Alternatively at the SAFEMM (Société Archéologique
Française d’Etudes des Mines et de la Métallurgie) meeting at Paimpont, in
Brittany, in November.
Peter
For arch-metals members - early discussion on this subject can be viewed in
the archive at http://www.jiscmail.ac.uk/lists/mining-history.html - just
search on cupellation.
______________________________________________
Dr Peter Claughton,
Blaenpant Morfil, nr. Rosebush, Clynderwen, Pembrokeshire, Wales SA66 7RE.
Tel. +44 (0)1437 532578; Fax. +44 (0)1437 532921; Mobile +44 (0)7831 427599
Hon. University Fellow
School of Historical, Political and Sociological Studies (Centre for South
Western Historical Studies)
University of Exeter
E-mail: [log in to unmask]
Co-owner - mining-history e-mail discussion list.
See http://www.jiscmail.ac.uk/files/mining-history/ for details.
Mining History Pages - http://www.exeter.ac.uk/~pfclaugh/mhinf/
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