For what its worth (and there is no need for these things to be similar everywhere), we have
a new (early Medieval?) site in Ireland where small bells were being produced. These are
not the large ecclesiastical handbells we looked at before, but small ones - from the size I
would guess for goats/sheep. They preserve some details of the brazing coat that we didn't
have at Confad. It would appear that the open end of the bell was not covered in clay; the
clay shroud rolls over the lip of the bell and terminates less than 10mm up the inside, with a
progressive but rapid dying out of the external vitrification over the in-turn (the bells seem to
have always been fired in an inverted postion). There is no sign of any object like the
"propfen" plugging this end.
Tim
On 19 Nov 2009 at 11:23, Anders Söderberg wrote:
> Hello again Sébastien, and everybody else,
>
> I do recognize the object at your picture. There's at least
> one similar object from Helgö, see http://hem.passagen.se/anders.sberg/9890.jpg
>
> This is an end-piece from a ceramic package from some
> metallurgical process where the iron object to be treated was
> wrapped in a protecting clay package before treatment. There
> are probably several processes where clay was used in this way,
> and I know two that so far have been identified - case
> hardening and brazing (usually of padlocks and bells) - and
> probably there may be a package-welding process around as well,
> but the ceramic remains from such a process haven't yet been
> identified.
>
> The "Propfen" could represent end pieces from treating tubular
> iron objects, as suggested at left in the picture 9890.jpg -
> perhaps from soldering together/brazing small bells.
>
> There are a few more examples from Bosau: check "Gebers, W.
> 1981. Bosau, Untersuchung einer Siedlungskammer in
> Ostholstein. V:1, Der slawische Burgwall auf dem
> Bischofswarder. Teil 1: Katalog. Sackau, H. (red) Neumünster.",
> tafel 22, page 120.
>
> Picture 4, 5 and 6 show similar end pieces. Moreover, picture
> 1, 2 and 3 show exellent fragments from brazing padlocks, with
> visible imressions of the locks, and pictures 8-16 show
> different examples of tubular packages, probably deriving from
> case hardening.
>
> Anders
>
>
> >----Ursprungligt meddelande----
> >Från: [log in to unmask]
> >Datum: 18-11-2009 21:18
> >Till: <[log in to unmask]>
> >Ärende: Re: Ang: Re: slag rods/tubes on archaeological sites
> >
> >An image is avaible here: http://www.zoyd.info/public/bouchons.jpg.
>
> >These two examples are from a large gallo-roman rural smithy
> in
> >Etagnières/Switzerland. As far as I can remember, some other
> pictures
> >were published in the monographs of Haithabu (viking/Germany)
> and
> >Dietikon (roman/Switzerland), but I don't have them at hand
> right now;
> >however, besides of the section, all of these items look quite
> similar.
> >I might put some other photographs online, if useful.
> >Cheers, Sébastien
> >
> >Anders Söderberg a écrit :
> >> It would be most interesting to see a few pictures of those
> >> "Propfen". Are there any available somewhere?
> >>
> >> Anders
> >>
> >>
> >>
> >>> ----Ursprungligt meddelande----
> >>> Från: [log in to unmask]
> >>> Datum: 18-11-2009 16:10
> >>> Till: <[log in to unmask]>
> >>> Ärende: Re: slag rods/tubes on archaeological sites
> >>>
> >>> Dear all,
> >>>
> >>> I guess we may be talking of different things, but I
> thought
> >>>
> >> I might use
> >>
> >>> this occasion to query about some slightly similar pieces
> for
> >>>
> >> which I don't
> >>
> >>> find any satisfying explanation. We repeatedly found some
> clay
> >>>
> >> rods a few
> >>
> >>> centimetres long in slag assemblages of gallo-roman
> smithies
> >>>
> >> in Switzerland
> >>
> >>> (I know of at least 6 individuals from three sites in
> >>>
> >> Switzerland). The
> >>
> >>> surfaces are blackish and slagged on a very shallow
> surface.
> >>>
> >> They have an
> >>
> >>> oval or rectangular section of perhaps three or four
> >>>
> >> centimeters; one
> >>
> >>> extremity generally shows a slight bulge. The pieces are
> >>>
> >> altered on all
> >>
> >>> surfaces of this extremity, which was obviously exposed to
> a
> >>>
> >> certain heat,
> >>
> >>> although the alteration is restricted to the surface. One
> of
> >>>
> >> these pieces
> >>
> >>> was analysed some time ago by Marianne Senn; the surface
> was
> >>>
> >> strongly
> >>
> >>> enriched in iron, and the clay seemed to be similar to
> that
> >>>
> >> used for crucibles.
> >>
> >>> Similar pieces have been found in quite large numbers in
> the
> >>>
> >> Viking site of
> >>
> >>> Haithabu, and two or three others are known from two French
> La
> >>>
> >> Tène sites. I
> >>
> >>> guess there might be many others, but they are quite
> difficult
> >>>
> >> to identify
> >>
> >>> in large slag assemblages; besides of the particular
> >>>
> >> morphology, the
> >>
> >>> material looks just like the usual sandy-clayey slags;
> like
> >>>
> >> these, they are
> >>
> >>> probably quite friable.
> >>>
> >>> The pieces I know of are always clearly associated to
> smithies
> >>>
> >> in sites
> >>
> >>> devoid of smelting activities. In german, they have been
> >>>
> >> called "Propfen" or
> >>
> >>> "Zapfen". Obviously, they were used to block some
> rectangular
> >>>
> >> or ovoid
> >>
> >>> opening (an air inlet?) on one side of the hearth exposed
> to
> >>>
> >> the fire; but
> >>
> >>> why would there be a need to block an air inlet in a
> smithing
> >>>
> >> hearth (and
> >>
> >>> what is more, from the inside)? Although they seem to be
> very
> >>>
> >> rare, I find
> >>
> >>> it astonishing to find such pieces all over the time from
> Iron
> >>>
> >> Age to
> >>
> >>> medieval times. I just can't figure out to what particular
> >>>
> >> practice they
> >>
> >>> could be associated; I wonder if somebody could come up
> with
> >>>
> >> some
> >>
> >>> explanation for these objects?
> >>>
> >>>
> >
> >--
> >Sébastien Perret
> >Mineralogy and Petrography, Department of Geosciences
> >University of Fribourg, Chemin du Musée 6, CH-1700 Fribourg,
> Switzerland
> >phone: +41 (0)26 300 89 40
> >mail: [log in to unmask] <mailto:[log in to unmask]
> ch>
> ><http://www.unifr.ch/geoscience/mineralogy/archmet>>
--
Dr Tim Young
Email: [log in to unmask]
Web: www.geoarch.co.uk
Phone: 029 20881431
Mobile: 07802 413704
Fax: 08700 547366
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