Wednesday, 6 May 2015

The Iceni hypothesis — part fourteen

As its listing does not say "what appears to be silver", am I to
assume it was XRF tested? My teacher in museum cataloging,
Lew Burke at Glenbow Museum certainly drilled that habit
into me. I was eager to have the pellet and ingot analyzed
thusly, but was still surprised to discover that neither was
silver. Other gold ingots are also present in this hoard.

My Iceni hypothesis has limited application: it requires a coinage that was issued over a long period and has a great number of dies. Most pre-Roman coinage was issued for a specific reason such as a war or a large payment to another state. Only the very small denominations were issued for local day to day market purchases, although even these might travel some distance, and some states never even had such a coinage.

When I first received a representative collection of the finds at the Dobunni site, I was thinking in terms of metalworking or recycling of coinage because of the Dobunni coins, pellets, and ingots. I did not think that the site was a mint, though, as there were no coin blanks or ceramic coin blank moulds in the sample. Also, most of the finds seemed later deposits of, sometimes, earlier material. I thought that the coins, pellets and ingots were all materially connected. So it was a surprise to discover that the ingot was white gold in the range of the Iceni wolf staters, but contained an alloying proportion (3.7%) of tin, and that the pellets were not silver but an exceptionally tin-rich potin (46.6%).

When I first heard about the finds, it seemed to me that the site was used as a Druid council site because Dean told me that the coins were scattered ever the original surface, and when he confirmed other features of the site that I suggested would be there if that were the case, I was sure of it. There were springs in the vicinity and lots of animal bones from feasts and it was distant from any known Roman site.

Pondering the significance of finding Norfolk wolf stater-like white gold in Dobunnic territory (which was a red-gold area) made me wonder about a route between the Iceni and Dobunni territories and that lead to me looking at the Jurassic Way. I then noticed the distribution of Dobunni ANTED coins seemed to stretch toward Norfolk and that there was, apparently, another ANTED at the other end of that route. I also noticed that a great deal of very well-known and high status objects were found either side of that route (which ended up in northern Britain after turning in the area where Iceni coins could be found).
Also supporting this line of thought were some finds of Thurrock type potins along the direction of the Jurassic Way (Fig. 55). Succumbing to a little deductive reasoning, I remembered that the purity of the metal was related to the distance from its source. I knew that tin was from Cornwall and that stray finds of Thurrock potins are known from Dobunnic territory and I even had one in the sample. Its tin content was also higher than usual but not as high as the pellet. Could the pellet be the form in which tin reached the Dobunni, with its copper content providing the required seigniorage for its traders? I imagine that there was at least one intermediary between the Cornish tin mines and the Dobunni. Likely it was members of the Dumnonii (both Dob- and Dumn- come from the same root as Dubn- and signify "the deep" or the Underworld). The Dumnonii were not so much La Tène as an earlier Celtic culture and they did not use money. Another cultural connection between neighbours is the Iceni and Corieltauvi who both made great use of the boar as a main device on their silver coins (although the scyphate gold coins of the Corieltauvi are an exception and are the only Celtic gold coins which bear the figure of a boar as a main type instead of a subsidiary type.  The much earlier Witham shield which belonged to a spearman also, originally, had the boar as its main device. The silver coins start by copying a Roman Republican denarius showing the speared Calydonian boar. The Celtic equivalent myth is that of Diarmait and the boar of Benn Gulbain.

What has continued to bother me, however, is the tin content in the ingot. We have yet to have an analyzed wolf stater with significant amounts of tin, and that would unusual for any Celtic gold coin. The Dobunni had no problems in keeping tin out of their own gold coins, so we cannot look at the content as an impurity and the ingot has about twice the amount of tin that is found in the bronze coins of Massalia which also show the butting bull of the Thurrock potins. One analysis has identified the source of some copper in Massalian bronzes as being British as there is still a higher Co to Ni ratio visible in the coins, and as Gaul had lots of its own copper and had no need to import the distinctive British copper with its cobalt impurity, then the tin, itself, must have come to them before 50 BC from Britain, and already diluted with copper.

I am currently of the opinion that the Dobunni white gold ingot was a metal alloy created by the Dobunni for use in Norfolk in (mainly) torcs. While it is recorded that tin is present in the later Snettisham torcs, the only analyses I have found so far just give the Au, Ag, Cu main alloying metals and do not include details of the tin content or any of the trace elements.

Tomorrow, how things should be recorded.

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