In case anybody missed this, here is Pete's photo of a small fragment which he found -- derived from a barrow near the Avebury Sanctuary. Could this be a fragment of meteorite? Or is it a bit of clinker from the smelting process? If this is Bronze Age I suppose the latter is possible......
From Pete:
https://fbcdn-sphotos-g-a.akamaihd.net/hphotos-ak-ash3/559489_10151514988553022_419258203_n.jpg
I found this near the Sanctuary at Avebury.
An animal had excavated out a lot of material from the center of a barrow including two types of pottery, a polished bone pin and several strange types of stone. I left them there.
PeteG
25 comments:
I would suppose Pete would have recognised clinker when he saw it? Although why remnants of iron working would be in a barrow is another puzzle.
I am puzzled by the Danebury find. In the iron age one might expect a piece of ore to go into a kiln. Why place it in a grain pit? Perhaps the meteorite was expected to transfer magical properties to the beer....
I like to think our neolithic ancestors would have seen a falling star as a wondrous thing. But where did these meteors fall, and when?
I suppose Mike Pitts would likely be one archaeologist who would take a lively interest in what you found at this barrow somewhere near The Sanctuary. Mike lives at nearby Marlborough, excavated at The Sanctuary in the last 20 years or so, and edits "British Archaeology" and its accompanying website. Maybe Pete already has had contact with him over the years? Mike was also the Curator of the Alexander Keiller Museum at Avebury.
I've seen plenty of clinker/slag but this was like nothing I've seen before.
It has the classic thumb print indentations that some meteorites have.
I first thought it might be Niedermendig Lava as there has been a lot of this found near the Sancuary and along the Kennet Avenue.
It was after watching the Sky at Night that I remembered it and looked back though my photos,
PeteG
I prefer to take such finds to a proper expert in meteorites.
I wouldn't ask an astronomer about an excavation trench and don't believe anything archaeologists say about astronomy or geology etc.
PeteG
Amen to that. By the way, Colin Pillinger has spoken and written about the Danebury find -- I recommend a watch of his RS lecture.
Oh that was a good thought.Niedermendig lava certainly lots of vesicles but usually visible cpx phenocrysts. I agree not German.
I thought I had a bit from Stonehenge but it was dirty siliceous sinter.
Niedermendig Mayern lava are distinctive and very pretty in thin section.
It does look slag like to me.
Myris
Pete, do you know the context for the Niedermendig stones?
They were reputedly highly prized as grinding stones and traded in the Neolithic. The European Celts liked them as did the Romans.
I went to the AKM on their open day to have a look at the lava
http://www.peteglastonbury.plus.com/Niedermendig.jpg
Cunnington said in her notes that around 80 small pieces were found around the Sanctuary.
After seeing the one's found on WKA I dismissed the piece I found and never thought about it being a meteorite until recently.
PeteG
this barrow has been extensively ploughed so if this is clinker/slag then it could have been dragged here from any part of the surrounding field at some point.
I haven't seen slag like this before in the area but if Rob thinks it's slag then I'm happy with his opinion.
I'll see if I can find it again.
PeteG
I do but stress that it is an id. from a photo.
Niedermendig Mayern lavas were milestones up to the 19th cent.They are very common in all sorts of contexts much is used as rubble infill in post Roman sites.
They are rather exotic basaltic rocks associated with a large circular meteorite strike (I think)'Really lovely rocks full of strange but difficult minerals the feldspathoids.
Oddly Niedermendig lava is rare as pot temper.
M
Pete
couldn't bring up your item using your Niedermendig.jpg reference, can you advise?
Tony
I don't know how to make the link live on here but copy this line into your browser.
PeteG
http://www.peteglastonbury.plus.com/Niedermendig.jpg
Danebury excavation reports.
I haven't yet found any ref to the meteorite,
PeteG
http://archaeologydataservice.ac.uk/archives/view/danebury_var_2003/
Apparently some of the Niedermendig pieces came from the lower part of a posthole Cunnington excavated at the Sanctuary. The context is reported as being 2500 BC. Some people use the find to reinforce the view of long distance neolithic communication, in this case to Europe south of Cologne..
The pieces Pete shows look small and regular. Perhaps hand tools for polishing stone axes or similar? The usage for querns is - I think - more into Roman times and was revived in the middle ages.
@GCU. From what I read the Niedermendig lavas are of volcanic origin, or are you pulling my legs.
It is of course millstones not milestones. How I hate auto correct.
M
No I was not kidding but wrong!!
I thought that I had read soemwhere that Laacher See was an astrobleme. Blame on early onset Altzheimers.
Should have checked.
So strike that meteorite strike.
M
I would imagine that Ros Cleal and her colleagues would be the fount of all knowledge on artifacts and all things at The Sanctuary. She did the major SIIL composite report on Stonehenge In Its Landscape in the '90's but has been Curator of Avebury Museum for many years and knows that prehistoric landscape very well. Based at the Alexander Keiller Museum in Avebury. Check out the National Trust website.
I've been waiting 2 1/2 years for Ros Cleal to get back in touch after requesting to see the polished hand axe fragment I found on the Kennet Avenue dig in 2003.
The NT at Avebury are only concerned about getting punters into the Manor house and doing paid tours for tourists.
Research for locals is not on their agenda as it doesn't make a profit for the NT.
PeteG
Perhaps Chris (rather than Pete) might like to contact Ros, to follow up what he's already researched. Her colleague, Ms Nick Snashall,an expert on early prehistoric artifacts, may also be able to provide useful info. She is also involved with the Stonehenge National Trust land. I think Nick may be a better bet for a useful response. I used to be a volunteer in the Avebury Museums.
Mike Pitts may be contactable via his website or through British Archaeology magazine at:-
editor@archaeologyUK.org
Apologies for gatecrashing another comments thread, but I hope this article in Current Archaeology will at least be of interest to the learned and thoughtful contributors here: "Vespasian’s Camp: Cradle of Stonehenge" - http://www.archaeology.co.uk/articles/features/vespasians-camp-cradle-of-stonehenge.htm
The gist is that evidence of long-term Mesolithic activity & settlement has been found only about a mile from Stonehenge. A fascinating (and generously illustrated) article, I thought - and one which more than makes up for not being able to see the 'Flying Archaeologist' tv programme later this evening.
I'm certain it is slag, probably from Iron smelting. I have found a lot of it at All Cannings Cross and have an identical piece on my desk as I type. I used to hope it was from the early iron age smelters we had here but it is probably from the use of Basic Slag as a fertiliser in the last century. Remember there were Iron works at Seend so it was a local byproduct. Cinders were also used as hard core in field gates.
There was a sizeable Roman settlement on the slopes of the hill on the opposite side of Silbury Hill [relatively close to The Sanctuary].
"....pits are dotted around the settlement[revealed by geophysics in 2006 & 2007], and anomalous readings in one area may suggest some form of industrial activity, perhaps metalworking." Quote from 'The Story Of Silbury Hill',published by English Heritage, Jim Leary & Dave Field, 2010. £14.99.{both these writer-archaeologists featured in the BBC programme "Stonehenge From The Air", the subject of a slightly later April Blog item.
Mr Daw
Please email Myris I want to ask about some sarsen debitage I am looking at. On my website.
I cannot find your email address on your blog just twitter!
M
There is one other option, which has been a point of contention between those who have not invested time in reading the literature on anomalous glassy materials found in abnormal contexts and those who have decided to impartially-investigate their various chemical and physical properties: you may have found a rock or clay soil, surface-forming fulgurite, which is how sediments vitrify when water-saturated, of low porosity, colloidal, and conductive [clay-rich], especially those sediments associated with limestone, chert, shale, siltstone, or various argillaceous sedimentary bedrock. Any locale where marshes occur and ancient glacial and/or pluvial lakes may have also been present, lightning will often produce fulgurites that are vesicular, glassy, and slag-like, sometimes - when fresh - with a thin blue-grey metallic surface glaze and additionally bearing silicide-rich (but of much lower density and weight than similar slag), lapilli-like droplet and filament structures (exogenic fulgurites), which occasionally are found in association with [glassy, often slag-like] rock and clay soil fulgurites.
All fulgurites (except for some exogenic fulgurites, that will resemble impactites and tektites in these exceptional circumstances) will bear some invariant features consistent with electrical branching and tunneling, but do not necessarily develop a central tube-like void.
Since slag is rarely of interest to those who are not directly analyzing material with known industrial sources, and since so few researchers have pursued dedicated study of the variety of fused materials that occur in soils where many wet and conductive mixed sediments are common, a shamefully-limited number of images of such materials have been published and/or are available through online resources. This misconception is pervasive even among geological and planetary scientists, who usually dismiss such material by simple resemblance and geographic associations as common slag with no further investigation, since it is true that fulgurites like these are known to be found in areas that also, coincidentally, have hosted extensive mining and refining of metals in some reasonable proximity. Geologic provinces that are thunderstorm-prone may often also bear rich ores, and also tend to have the aforementioned varieties of compact, hydrated, clay-rich soil, chemically as a consequence of weathering of these mineral assemblages and especially due to the presence of abundant fresh surface water in conjunction with complex argillaceous sediments - mineral wealth and water being crucial resources that have attracted urban populations for millennia.
The dynamic charge-building and separating mechanisms that prevail on the ground for the production of fields that "shadow" the electrical potential of a thunderstorm may be enhanced where hydrocarbon, carbonate, and metal-rich saturated sediments and rock occur principally, and spring activity and aquifer distributions in these geologic contexts is also optimal for electrical conductivity facilitating terminal ground cancellation or inversion of electric potential differences; both springs and precipitated mineral deposition tend to occur near unconformities, whether from faulting with subsequent hydrothermal activity or glacial erosion with post-glacial lacustrine and alluvial infilling.
To test the fulgurite hypothesis (which I believe to be the most likely explanation, given the relative inadequacy of any other set of associations), look for other signs of lightning ground discharge activity in the area. This effort is greatly assisted if one especially focuses on observations from local trees, such as patchy defoliation of trees with chaotic stunting and denuding of surface plant cover, bifurcated/split tree trunks, stepped or linear fissures running longitudinally down trunks, loss of bark or branches, "bleached" or charred bark, etc. Also, you may find hard vesicular carbon-rich objects where such clay soil fulgurites form, as humic or plant-derived surface carbon seems to electrolytically self-reduce when lightning-affected, forming condensed masses that resemble smelting coke, but have a peculiar and homogeneously-spongy/glassy texture - with incipient branching and compact, lichen-like micro-branching "fabric" - and increased hardness relative to coal and refinery waste products.
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