The previous posting on a documentary about the Mitchell-Hedges (M-H) crystal skull seems to have provoked a lot of debate (on the blog and on the forum) and Philip Coppens was good enough to point out the response from the custodians of the skull so I thought it worth doing a full follow-up.

Before I start I should state for the record my thinking on this issue. I am* a geologist and archaeologist and so am very interest in the conjunction of rocks and archaeology. The crystal skull is a case in point - the New Age trappings that it has gained don't retract from the fact that it is an amazing artefact. I was more than happy to accept that this was the product of centuries of hard work but I will admit this could have been coloured by previous looks into this field, as I had concluded that the many claims for the use of advanced technology to produce amazing artefacts not only give little credit to the impressive skill displayed by ancient artisans but also can't take into account the vast amount of manpower and/or time that could be invested into a project (see my look at stone jars for more on this). The skeptical might say this led me to accept the claims about the skull without looking too closely but it is a reasonable conclusion based on the available evidence, and one I was prepared to adjust if new evidence presented itself - which it has.

Anyway on with the Mitchell-Hedges' site's response to the documentary. Their main problem with the analysis is:

The gravest of errors committed by the documentary is that it accepted the false premise that pre-Columbian cultures did not have any tools to make the skulls. It is none other than Michael Coe who has said this statement should not be taken as dogma, yet it is precisely that which several researchers, whether Jane Walsh, Margaret Sax, or television producers such as those making this documentary, hold.

This isn't the point. I think most people would accept that such an item could have been made by pre-Columbian civilisations just that it would have taken an awful long time to make (it is certainly what I thought), which is in line with other items of amazing stone work from the ancient world - they were prepared to invest vast amounts of time and effort to produce artefacts. This wasn't the main point of the study of the skull - what it showed were clear signs of modern tool marks. So it wasn't that they couldn't have done it -it was that the tool marks appear to show they didn't (although see below for more discussion on the tool marks).

They also say that the documentary was factually incorrect in reporting that he bought the skull before the auction. That is fair enough, although the important point remains, he bought the skull and the evidence they use to demonstrate this factual error is interesting as it does seem to support the idea the skull wasn't found by Mitchell-Hedges as he makes no mention of the story that would later emerge in correspondence written at the time:

The Sotheby’s sale was not reported correctly: Mitchell-Hedges did buy the Crystal Skull at auction for £400, outbidding the British Museum. It was reported in the daily newspaper of the time. Also in a letter to his brother in December 1943 he states: “‘The Collection’ grows and grows. You possibly saw in the papers that I acquired that amazing Crystal Skull that was formally in the ‘Sydney Burney collection’. It is fashioned from a single block of rock crystal, exactly life size. Scientist put it at around 1800 BC and they estimate that it took five generations passing from father to son to complete. It is anthropologically perfect in every detail. A superb piece of craftsmanship. There is only one other in the world like it which is in the British Museum, and it is acknowledge not to be as fine as this”.

In another letter he says “this is one item that no amount of money will induce me to sell and I have had three American museums trying [...] The Anthropological journal Man has nearly devoted an entire issue to it.” In the same letter he refers to the Skull as being “world famous”.

They argue that it seems odd that he would have gone out of his way to buy the skull at a furniture sale but I think most people would move heaven and earth to get their hands on the item. What is clear is that going by his own writings Mitchell-Hedges was making no claims about finding the skull - this is also consistent with what he says in his 1954 autobiography (which only makes a minor passing reference to the skull and no claims that he found it), that story appears to emerge much later (a retcon even, as the first 20 years of its documented existence certainly don't include Mitchell-Hedges discovering it in 1924).

They also pick up this point:

Finally, the documentary’s conclusions were muddled in the extreme. It is a known fact that the skull existed in 1934 (as indicated in the MAN 1936 article that was used in the documentary), yet the documentary seems to allege that in 1924 the technology did not exist to create this skull, when Anna said she had found the skull

They didn't though. The scientists were quite clear that the tools would be available from the end of the 19th century. The documentary included comments from people who said since the technology didn't exist at the time the skull appeared they must have been made by aliens/Atlanteans. What struck me at the time that the documentary had been edited to make them look foolish - cutting straight from the revelation that the tools were recent and were around before the skull was made, to people putting forward wild ideas on how they could have been manufactured in a hi-tech manner in the past.

Here is an approximate transcription of the conversation (they talked over each other round about the cutting part but you can get the gist of it from here - don't believe me? Then watch for yourself):

Bill Homann: This is not cutting? This is more polishing?

Jane Walsh: No. That's cutting.

...

Jane Walsh: Probably the kinds of very fine carving tools that artists used, but also the kind of mechanised tools that were available even to dentists, by the turn of the century.

That seems fairly clear and unambiguous. It shows signs of cutting with tools that were only available from the end of the nineteenth century.

Of course, there is another problem - there is no evidence that the skull was found in 1924, which opens up another decade for the window of manufacture.

This isn't to say that there weren't problems with the documentary (although whether it was both giggery and pokery or a way to aid narrative flow that went awry isn't clear) but not only do the two core arguments still stand (that Mitchell-Hedges bought the skull and that they show signs of modern manufacture) but the information given out by the official site actually supports the first point - Mitchell-Hedges' writings at the time make no mention of having found this skull. Their statement made about the results of the tests is demonstratably incorrect - the modern tools were available before the skull appeared (just watch the video).

They do raise the point that only a few hours were spent on the skull:

Furthermore, the full verdict of the Hewlett-Packard and British Museum claims – both of whom did extensive testing on the skulls, unlike the few hours Walsh has spent with the skull – were not all fully put together and explained, as if they did not matter.

This is true and I know we'd all like the skull to be given a full round of tests as there are a lot of new tools that can be brought to bear on this (as well as more comprehensive comparisons between the M-H, British Museum and Smithsonian skulls). I fear that the provisional results showing clear signs of recent manufacture might put people off from further testing and it would be a shame if the documentary makers have given them the ammunition they need to shoot down the idea of further tests.

So in conclusion does this mean the M-H skull wasn't made in antiquity? No. Science is like that, dishing out absolute truths - it is more of an ongoing narrative. What the tests do appear to show (I'd want to see it written up for publication before I was happy with it) is that they are were made using modern tools, which would tend to tip the balance of probabilities away from it being a Pre-Columbian artefact. Equally this is not the end of the story, it is the start.

So where do we go from here? Well what I'd like to see is:

• Further tests - a quick run under the SEM for a TV show can't compare with a lengthy investigation using the fancy tools they have to hand. XRF looks to be a good one for identifying the type of abrasive used.

• Comparisons with the British Museum and Smithsonian skulls - does the M-H skull show identical marks? Are there any clues that can be gained?

• Comparison with other artefacts - a rebuttal from earlier this year on the M-H skulls site draws on statements from Professor Michael D. Coe and they say "Wafer-thin obsidian ear-spools are now known to have been made using some rotary carving equipment and to be dated to the Aztec/Mixtec period." If so they need to be analysed and any marks compared. Of course, we may be getting ahead of ourselves as there is an article in press (for the Journal of Archaeological Science) which will describe the tests on the British Museum and Smithsonian skulls and they should cover the comparative material they used.

So we'll see what happens. As it stands things don't look good for the M-H skull, but we really need to see details of all the analysis that has taken place and see how that stands up. Note that things could always swing in completely the opposite direction - we won't know until we see the details of the study what they compared the tool marks too. In theory, they could have dropped the ball and other studies may emerge showing similar marks on material known to be pre-Columbian. Having peer-reviewed a few papers for prestigious journals, I can't see how an article would get published in the JAS (the leading journal in the field) without covering those bases,

On a slightly broader front I would also have liked to give Jane Walsh the chance respond - the M-H site says "Jane Walsh herself is probably not all too pleased either by the words put in her mouth, namely that she was the one that uncovered the 1943 Sotheby sale records for the skull, or the implied references to the MAN 1936 article discovery" and her views on this would be interesting. However, I had a look around and couldn't find a contact address, but she is always welcome to drop me a line (for my email you can click on my name below).

So there is plenty of mileage in this story and I'll be keeping a close eye on developments - the next big one being the paper in the Journal of Archaeological Science and I will be casting my beady eye over that when it comes out.

* Was? I assume it is a bit like being an alcoholic or Catholic - I might no longer "practice" but it always stays with you.