Hi Tim,
That's some interesting info - and perhaps a reason to search
for other sorts of objects than bells here, or even for
another
workshop process? Or perhaps the wrapping practices could have
differed from time to time and at different geographical
locations?
The question still seem to be very open for new suggestions.
Anders
>----Ursprungligt meddelande----
>Från: [log in to unmask]
>Datum: 19-11-2009 11:35
>Till: <[log in to unmask]>
>Ärende: Re: slag rods/tubes on archaeological sites
>
>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:sebastien.
[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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