Happy New Year to all Arch-Metals Members
Bibliography +
I have at last had a little time add some new entires to the
bibliography. These are only on the Oxford version of the pages as the change
from mailbase to JISC has made it more difficult to add and edit web pages. But
the reorganised pages will be added to the arch-metals files as soon as I have
checked all the links work correctly.
The additions consist of the papers in Giumlia-Mair A. 2000. 'Introduction:
Archaeology and Metals between the Alps and Pannonia.' In Giumlia-Mair A. (Ed.)
2000 Ancient Metallurgy between Oriental Alps and Pannonian Plain:, 17-21
and two complete volumes of the Journal of the Historical Society (33 and 34).
See http://users.ox.ac.uk/~salter/met-new.htm for the full list.
One of the articles in volume 34(2) Mack et al was the source for an article in
the Christmas edition of the New Scientist (No 2270/71 p7). This relates to the
discovery of small steel ingots at Hamwic, Saxon Southampton. This ingot had a
relatively homogeneous carbon content 1-1.5%, low slag inclusion content, a feature
also seen in steel artefacts from Saxon artefacts of Southampton and York.
They go on to suggest that a two stage process was being used in which cast iron
was deliberately produced and then decarburized from the liquid state in a
second process.
I am not totally convinced by this, as the same process can occur naturally
within the bloomery furnace, all that is required a bloom-master with the skill
required to control the bloomery temperature, and then to separate out the
different types of metal from the bloom - a technique used in the tatara
furnaces of Japan and the products of the Juleff's wind powered furnaces in Sri
Lanka also produced zoned product. Also, it is noticeable in the hundreds of
object that I have examined that there is a strong inverse correlation between
the carbon content and the slag inclusion density.
On the other hand, if they are right, the technique is older than the Saxon
period, as Roman Carmarthen has produced a block of relatively homogeneous
hyper-eutectoid steel from a 2nd century smithy.
In the vein of archaeometallurgy for a wider audience Paul Budd produced an
article 'Meet the metal makers' which gives one possible view of the
introduction of copper alloy metallurgy during the chalcolithic and
Bronze Age in te British Isles( British Archaeology No 56 Dec 2000 -12-17). The
article, starting with the Castell Coch hoard (circa 2000 BC) gives a very
quick outline of the discovery of copper and its first smelting, to move on to
the use of arsenical copper, with reference to Ross Island, Ireland - the
source of arsenical copper and the later Welsh mines at the Great Orme mines,
Parys Mountain, Alderly Edge and Cwmystwyth which it argued that were producing
non-arsenical metal to dilute the Irish metal. However, it suggested on the
basis of the lead isotopes and nickel content the copper in the two bronze the
objects in the Castell Coch hoard that the copper came from Cornwall (as well
as the tin).
The article then becomes confusing, as it then states that bronze
objects were not made in Cornwall but tin ore was transported to the area of the
Great Orme to be added to local copper using a cementation process! Presumably
this refers to a later period in the BA, but this is not stated. Unfortunately,
for his argument some of the ores from the Great Orme used in the Bronze Age,
circa 1500BC are also radiogenic! As are other possible ores sources in Europe
as might be expected as they are part of the same Variscan metallogenetic province
the Moldanubian zone of this province, running from Galicia, Spain through to
Central Europe, is characterised by high uranium contents. With evidence of
Bronze Age activity from a number of the ore fields within this province now
beginning to appearing appear, and the lack of evidence of British bronzes with the
distinctive South-Western trace element pattern seen later in prehistory, I
suspect it is a little too early to conclude that Cornwall was the source of the
earliest British Industry. However, we do know that they were smelting tin to metal
by circa 1600 BC. So Paul's last point, given the mineral wealth of Devon and
Cornwall in the form of it's large tin deposits, it is surprising that there were
no obvious signs of wealth in region, is to the point. Then nothing has changed in the
last 4000 years, still the primary produce of the South West goes up country
(cattle, sheep, milk, fish, china clay, and various vegetables) and the locals
get very little in return (and in the last few years even loose money in the process).
I seem to remember when I was young, a long time ago, that most of the local produce
in the shops in Plymouth (other than on the market stalls) had been up to London
and back.
(Plymouth is on the Devon Cornwall border, for those that do not know the geography of
Britian - not 280 kilometres to the east - sorry that is a hangover from when I
first came to Oxford where a large number of people thought that Plymouth and
Portsmouth were the same place!
Getting back to Bronze Age copper mines (or possibly not) the Journal of the HMS
on the Bronze Age mine at Cwmystwyth (not its date this time) but what was
being mined! David Bick (JHMS 33.1 p7) argues that the Bronze Age mining
activity in mid-Wales was for lead and silver not copper. His arguement is
based on the fact, that a number of purely lead mines have stone axes
associated with them. Tim Mighall et al, in vol 34.1 p1, argue that at
Cwmystwyth at least the trace element record in the surround peat profiles show
that it was copper that was being mined and processed.
These together with a number of other, to me, equally interesting articles make
these most welcome volumes. The editors should be congratulated in getting the
chronological and publication dates back in in synchonisation in such an
interesting manner.
Finally, as I have to get back to 21st century material science. I have, with
the kind permission of the author put Tony Oldham's review (first posted to
mining History) of "King Copper: South Wales and the Copper Trade 1584 - 1895"
by Ronald Rees on the review page at http
Chris Salter
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Materials Science-Based Archaeology Group,
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