David
When writing up the 10th-century evidence for bell-casting from Gloucester I compared the metal analyses with eight other bells from a variety of places, mainly in Britain (Bayley et al 1993a). All the metals were high-tin bronzes with low lead levels. In none of them is the presence of antimony noted. Normally I use the presence of large amounts of lead together with percentage levels of arsenic and/or antimony as indicating the metal came from a cast domestic vessel such as a cauldron or skillet. On foundry sites this difference in composition can be used to identify whether bells or domestic vessels were the products (Bayley 1993b). Recent work (Dungworth and Nicholas 2004) has confirmed the widespread use of antimony-rich copper alloys for domestic vessels in medieval and post-medieval times.
Conventional wisdom says that the metal of which a bell is cast has to be hard in order to get a good ringing tone. It is notable that for the bells for which I found analytical data, the tin content increased from under 15% in the 10th century to 20-24% in the high medieval and post-medieval periods. Antimony and lead have a deadening effect on the ringing tone - if hit, a cauldron would sound 'clunk' rather than 'ping'!
Bayley, J, R Bryant and C Heighway (1993a) 'A tenth-century bell-pit and bell-mould from St Oswald's Priory, Gloucester'. Medieval Archaeol, 37, 224-36.
Bayley, J, J D Richards and D M Ranson (1993b) Metal founding (186-200). In: J D Richards, The Bedern Foundry. The Archaeology of York 10/3. London: CBA.
Dungworth, D and Nicholas, M (2004) 'Caldarium? An antimony bronze used for medieval and post-medieval cast domestic vessels', Historical Metallurgy 38(1), 24-34.
Best wishes
Justine
Dr Justine Bayley
English Heritage
Fort Cumberland
Eastney
Portsmouth PO4 9LD
Phone: +44 (0)2392-856794
Fax: +44 (0)2392-856701
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-----Original Message-----
From: Arch-Metals Group [mailto:[log in to unmask]] On Behalf Of david bourgarit
Sent: 27 June 2008 15:09
To: [log in to unmask]
Subject: medieval bronze bells in Western Europe
Dear list members,
I am looking for elemental analysis of medieval bronze bells (from
churches) in Western Europe. Could anyone provide me with references
and/or data.
I was told in particularly that the Sb content could decide the way the
bell had to be hitten...
thanks
--
Merci d'envoyer UNE COPIE à mon adresse personnelle, [log in to unmask], la moitié des courriels ne me parviennent pas à la présente adresse
David Bourgarit
Responsable des études en métallurgie
Centre de recherche et de restauration des musées de France
tél:01 40 20 56 39
UMR 171 du CNRS
Palais du Louvre - Porte des Lions
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