Obsidian is a kind of volcanic glass and was highly prized for making certain kinds of stone tools. Obsidian forms at places of relatively small outflows of magma, or liquid rock. Small flows can cool quickly, which allows the formation of a glassy crystalline structure ideal for stone tool manufacture. Small flows also represent a small sample of well-mixed magma, and thus each little patch of obsidian may share a very distinctive chemical signature. This signature, usually identified by trace elements such as Strontium, Zirconium, Yttrium and Rubidium, then allows for the chemical fingerprinting of each source. Any obsidian artifact found, whether at a source or not, can also be “fingerprinted” and then compared to a catalogue of known obsidian ources. Since the artifacts don’t move around on their own but only through the agency of humans, the distribution of obsidian artifacts is a proxy measure for the movement and interaction of people. When you have hundreds or thousands of such artifacts and a large database of known sources, then you can start to see large scale, long-term social interaction emerge from the silent archaeological record. Most obsidian isn’t visually distinctive enough to sort out by eye alone, so these geochemical methods are essential.
So far, so Archaeology 101. I was really happy to find that Oregon’s Northwest Research Obsidian Studies Laboratory has a web site not which not only solicits business, but is a highly educational and informative site about many aspects of obsidian analysis, with a focus on the Northwest.
For example, they have a handy series of maps showing western United States known obsidian sources (as well as the latitude and longitude of these sources here and a simple google maps here – nick, fire up your truck, and GPS). Some of the detailed maps of Oregon are incredible – who knew how many distinct sources there were, so close together? Also, there sure are a lot of known sources in Washington State – why then is so much BC obsidian coming all the way from Oregon? Canadian sources are not yet mapped. They have some sample reports available for download, and some extensive bibliographies. Their FAQ is comprehensive and informative.
The research page contains a lot of interesting links, including analysis of Luther Cressman’s mysterious Kraft Dairy Fresh Caramels box of artifacts, and Bone Cave lava tubes. I was also intrigued to see that Obsidian Hydration is back on the table as a dating technique, and that this lab routinely does Fine-Grained Volcanics (basalts, andesites) X-Ray Flourescence as well – including a major source they place at Watts Point (near (Britannia Beach) but which is not mapped very clearly (see this page). Work on these “crappy coastal lithics” could be very cool: I am thinking of the apparent quarry site Parks Canada recently identified on the Gulf Islands, for example, and whether these lousy lithics were widely sourced or opportunistically scavenged from tills.
Incidentally, they are currently offering research support targeted at Graduate Students wanting to work on geochemical work in BC – this could be a great project for someone to sort out the various Edziza sources (reminds me, I have a lump of unsourced Edziza obsidian on my desk which I picked up in about 1984 at about 8000 feet). They also have a series of 360 degree panoramic views of some obsidian sources (e.g., Collier Cone) as well as their lab and so forth. They’ve even started a youtube channel.
A blog (not too many entries yet) contains the first written confirmation I have seen that the longstanding BC “Central Coast A” mystery-source obsidian is now known to be from the head of Kingcome Inlet, which is a substantial break through in understanding the distribution networks of NE Vancouver Island and the adjacent mainland. I heard about this through the grapevine but nice to have a little detail.
Sample analysis starts at 45$ and then decreases depending on volume. It would be great if there was a requirement for obsidian to be sourced during BC CRM studies — I know it often is anyway, but the marginal cost is minimal and the accumulated benefits could be enormous so why not make this a minimum requirement of a permit?
Anyway, this is a full and interesting site which goes well beyond the narrow frame of a commercial service and provides useful background information and exciting case studies to whet the appetite for more obsidian studies!
This is great news to hear as they sadly shut their lab in 2008 and have now reopened anew. I agree that the cost is minimal for the information one gets. However, the fact that a comprehensive quantitative sourcing study has not been conducted in BC may mean that your artifact won’t be linked to a source (which is also interesting, but only to some of us). Eventually though, more work may triangulate candidates for unknown sources and all these data will be interesting.
I’m sure Morley will be posting here about our obsidian results from the Williston area, but yes, there is a huge gap in BC data. We even sent in a sample of obsidian collected from Edziza by Matt and Darcy – but sadly no direct matches. We did get (from what I remember) at least two distinct sources though.
I think it worthwhile to test our samples anyway – at least then we will have a fingerprint once the source is found.
And yes, the price makes it appealing to do so!
I too am glad to know these guys are back in business. I recently saw an account of obsidian analysis done for a site in the lower mainland which had been sent to Chicago. They had no source data and thus had no matches – big surprise. It was reanalysed locally, and one thing of interest was that there was Edziza obsidian at the site, not a first for the lower Fraser, but pretty cool none-the-less.
If I recall on their web site, if you send a piece from a source they don’t already have, then the analysis is free.
I just updated the post at the very end, with an old spreadsheet I made ca. 1998 using Carlson’s 1994 data.
This is a hint of what we could learn: the watershed between Oregon sources and Central Coast/Chilcotin sources does not respect ethnoloinguistic boundaries but seems to be roughly along the northern margin of Hul’qumi’num territory. Not surprising, of course, considering this is a conflation of thousands of years of obsidian but it also doesn’t fit with the conceptions of the Gulf as an ecologically discrete zone with a necessary basket of Culture Types within it — or rather, ti cross cuts the Culture Types we know are there: some point to northern trade networks, others to southern trade networks
Note also how Shoemaker Bay has Oregon obsidian whereas its Gulf of Georgia “neighbours” doesn’t — perhaps it was implicated in west coast trade networks not Gulf ones? Even Garibaldi obsidian isn’t making it into the northern Gulf, or even to Bliss Landing!
Small and dated sample size and all that but still… Even with existing new data this could be very cool, let alone doing another sweep through and submitting more samples. OK no one else do this project it is mine, all mine.
R. L. Carlson 1994. Trade and exchange in prehistoric British Columbia. In: T. G. Baugh and J. E. Ericson, Editors, Prehistoric Exchange Systems in North America, Plenum Press, New York (1994), pp. 307–361.
Though Shoemaker has lots of Central Coast A/B, of course. Points to the greater proto-Salishan connections!
Also note the two sites with three sources: Marpole and False Narrows: suggestive of more diverse trade networks of this middle-Gulf sites? No Central Coast A/B south of the Marpole-False Narrows axis!
I don’t recall any Edziza obsidian showing up in Gulf of Georgia sites in Carlson’s catalogue though it wouldn’t really surprise me to see a bit of Edziza obsidian, but it would surprise me to see a lot of it, considering proximity to Oregon via Puget Lowlands, and, as I said, where is all the Washington State material — is there just not much of it overall despite the numerous fingerprinted sources?
I think its time to do more with the basalt/dacite as you say Q. I would be surprised is such crappy stuff on the coast is moved very far, but we really don’t know.
I’ll have to look at the Edziza report again, but from what I remember it was all very likely Edziza, but they didn’t have enough source material from which two of the various flows to be sure. Arcas’ samples from Williston came back all Edziza.
This thread is very timely. NW labs got our 2009 samples this morning; they went into the spectrometer this evening (as Roger says, either they are really excited or they don’t have any work!) and we should have some results by tomorrow. We only sent three samples this year from Williston. Two are what we are pretty sure are almost conjoining pieces of the same narrow lanceolate parallel oblique point. If the fingerprinting comes back a perfect match (within calibration error) then we will know the two halves really do fit. And in this case that is the main question, rather than where the quarry is. This is because if the two halves match, they are from locations on opposite sides of the valley 23 km apart, which would be the second longest refit in the world. I haven’t heard of anyone else using x-ray diffraction for this purpose before, so that may be interesting in its own right.
The third 2009 artifact sent for testing is a tiny retouched flake of red and black ‘mahogany’ obsidian that sure looks Oregon Glass Buttes to me! If so, that rock was carried an awefully long way! I drove that route this summer and it was a damn long way even on highways.
Did you know Glass Buttes was mapped as an ‘armoury’ location by the US Army in the 1800s because of its source material for arrowheads?
At least one of the consultants in the central interior has been building a database of results from basalt/dacite and I believe other rock types which they quite often run from sites they deal with. It might be quite useful for Williston area as well. There are also some recent results from the Arrowstone, Hat Creek and I think Maiden Creek quarries in the southern interior.
Similar work on the coast would be very interesting. In the Victoria area I am pretty sure that Grant Keddie has been collecting basalt-like samples from various beaches and might be a good starting source for raw materials.
Rudy Reimer has been doing a bunch of sourcing/chemical fongerprinting on samples from the Squamish area for his PhD. I believe there are some obsidian samples in his work, but also a lot of non-obsidian. Not sure where he’s at with this, but will be interesting to add his results to the larger mix when his dissertation is complete.
OK Morley, we expect a scoop on that here first, you know. Where is the longest refit? I’ve heard of some really long ones oasis to oasis in western Egypt….
I think I will send off some Gulf Islands “FGV”s along with the DcRu4 obsidian in a few days, just to start building an idea of what the stuff is, even.
TJO – Rudy comments here once in a while so maybe he can chip in.
Well, nothing definite yet: but the obsidian on the two halves is definitely from the same source, Edziza #3. To quote the lab:
“Alas, the amount of geochemical variability for an individual obsidian source combined with the analytical uncertainties that go along with XRF analysis makes it impossible to try and correlate at the artifact level (even two halves of the same artifact). ” So that won’t get us much further to verifying the match.
C.Skinner is suggesting doing some obsidian hydration to see if the layers are the same thickness on the outer surface and the break. If those match I think we can be confident that its a fit.
The world record for a refit is a few spall flakes in one spot and a quartzite core in another over 80 km apart, in California. The next furtherst may be the one you are thinking of Q, which is from some early Holocene stabilized dunes in Bir Safsal, southern Egypt. But the furthest was just over 1 km apart I think. This work (along with a global discussion of refits) was undertaken by the guru of long-distance refits, the aptly named Angela Close, who is at UoW in Seattle.
I’ll be opening an XRF lab here at SFU in the future…likely using a portable instrument to do work in the lab, the field and within First Nations communities…it works great on all sorts of materials (obsidian, dacite, rhyolite etc) as it has adjustable filters and settings depending on the material(s) being examined. Results of my dissertation will be published at some point, gotta do all this marking!
Hi Rudy — you know I was just wondering about those portable XRFs. Andy Roddick here has been using one on Tiwanaku ceramics, and I just saw this big study using one on obsidian from China – I wonder if they are comparable/compatible with existing databases or does one have to start again and re-zap all the sources? Happy marking!
“Please cite this article in press as:
Jia, P.W., et al.,
Moving sources: A preliminary study of volcanic glass artifact distributions in northeast China
J. Archaeol. Sci. (2010), doi:10.1016/j.jas.2010.01.027
i found a partial axe/spearpoint/knife made of obsidian when i was a kid(40 years ago).
it was found in coquitlam and was in an exposed bank of glacial till(undisturbed).
never did anything with it.
i still have it,would you be interested in having a look it?.
Ken, if you had a picture of it could you email it? If the glacial till is indeed undisturbed it could be a really interesting piece. qmackie at gmail.com
Thanks Al for letting me know about this forum.
In the Quesnel are we’ve been routinely submitting natural and cultural dacite samples resulting from CRM work for ICP-AMS since 2004. We generally select one flake from each site we identify if one is large enough (>5g). If it appears that more than one dacite type is represented we send additional samples. Our database is up to 125. We have two major local source areas that account for most of the dacite found at sites, but probably about a dozen other unknown sources.
I’ve seen data derived from ICP-AMS and XRF for Arrowstone and there appear to be significant differences in element composition measurements so I’m not sure how comparable results of the different analyses are. Anyone familiar with this problem?
Good to see this material being discussed.
One thing about Arrowstone is the size of the source – it is about 10kmx5km with dozens or hundreds of outcrops. It might be important to consider whether the Arrowstone results you were looking at were from the same or nearby locations, or widely separated.
You might find Nicole Smith’s MA from Haida Gwaii to be useful. I cant remember if she discussed the problems of matching results across methods, but I think it was a problem she encountered in her research. Maybe she will chime in on this discussion.
Hi APM, Ty
Thanks for the info, Ty.
It doesn’t seem to be geochemical, but this Montana thesis on Bridge River site might be of interest. (twoeyes sent to me recently). Though its notable as another recent heavy-on-ground-stone thesis that doesn’t cite my M.A., so really. The author blows hard on “property celts” which as far as I could tell was a concept without much merit.
Austin, Darrell Albert
A Lithic Raw Materials Study of the Bridge River Site, British Columbia, Canada
Thanks for getting me in the loop on this…lots of baby time these days – little fun geeking out time.
Ty – re the differences in element composition measurements between geochemical techniques….I didn’t address this problem directly in my thesis but do recall that you can’t necessarily compare numbers directly between techniques but that you can compare ratios of elements or percentages. The elemental counts can differ if they haven’t been normalized to an accepted standard to get ppm counts (in the case of trace elements as are commonly used in sourcing studies) or to weight percents for major elements (used to establish rock type). Generally though all labs should do this when reporting results. But even with ppm counts I think you need to be careful. I recall that for some techniques (like ICPMS) you can add an internal standard to the dissolved sample so you have a known quantity against which to calibrate the measurements and attain absolute numbers. For other non-destructive techniques though you can’t add an internal standard so the numbers you get are more relative to one another vs absolute numbers and dependent on the standard that’s used (or something like that?). That said, you should be able to compare data between techniques by using ratios of elements (Zr/Ti or Nb/Y for example).
Interestingly, sometimes even within the same machine the counts will change over the course of an afternoon. Such ‘drifting’ will be corrected for by the technician by comparing results to the universally accepted standards and by “massaging the data” they tell me. I think this all means that for sourcing studies maybe best to use the same machine and lab ideally? Curious to hear what others think….
Another general comment to add the discussion (sorry, I’m going to on here cause I so rarely get to talk about rocks with people!) is that when doing the geochem work on the volcanics (dacites, rhyolites, etc) it’s good to make absolutely certain that you actually do have a volcanic rock type. We found on Haida Gwaii that many of the materials previously identified as basalt were acutally metasedimentary rocks (of the argillite variety). Chemically, argillaceous rocks and shales have similar chemical signatures to volcanics (andesites, dacites, etc) so it’s conceivable that someone could be trying to get the signature for a presumed volcanic when actually it’s a metasedimentary rock! (They can look really similar). This happened when I was doing my analysis. Along with the archaeological samples for geochem analysis I included a sample we had collected from a possible source location (metasedimentary with clear bedding planes) that was 500 m south of the site. It plotted just like a volcanic – a basaltic trachy-andesite using major elements and a basaltic andesite using trace elements. Had we not known this sample came from a metasedimentary location we (including the geologists) would have erroneously called it, and many of the other archaeological samples, volcanic. After that we had to make sure that we were in the right family of rock types (volcanic vs sedimentary etc) before even thinking about sourcing….Anyway, just something to add to the discussion.
Sorry for the long entries, this probably goes against all blogging etiquette….
I am glad to see that our efforts (myself and Mike Willie, along with John Maxwell for emotional support) to reach the Kingcome Glacier in 2008 (sounds so cool) have come to some minimal fruition. The source we encountered is very close to the glacier (their is a siteform) reported and somewhat documented during several warm years when the area was not covered in snow, I believe it has recently become cool again, limiting access to the quarrying areas. Climate was certainly a factor in its use and distribution. If you search the canadian volcano website, you will find another obsidian source nearby at a lower elevation in Glendale Cove but I would expect the Central Coast ” B” to be on the upper Machmel River which flows into Owikeeno Lake. The flows may be late glacial (10-12 K BP?) in age. There is a well known travel route between Kingcome and Owikeeno… We are finding this Kingcome obsidian in the Kwakwakwakw area routinely ca 5000-2500 BP as Mitchell suggests. At any point…
I am loving this blog thang, thank you quentin!
You mean powered only by your courage, and a helicopter, you managed to get to the obsidian source 😉 . Anyway it is cool the central coast sourcing is coming together — why do you think B would be on Machimel River – because there is more B in that direction in sites?
Hi Nicole — thanks for taking the time to put in your experiences with zapping rocks and pressing the big red button that said, what, “Zot”, I think?
That’s pretty interesting about the meta-sedimentaries, does that mean they are just metamorphized sedimentary rocks which formed from eroded igneous ones of the same type? Amazing there would be no or not much change in the trace elements….
Nothing scientific to show that the Machmel may be the “B” source, just a guess ’cause its there along that major trade route. As for the helicopter, it was touch and go, we flew up the valley during an approaching storm and could not land at the usual spot so we waited below the glacier for a while with the valley walls (kame terraces) continually avalanche-ing around us… Interesting geology note, the kame terraces were collapsing onto a large bed of blue glacier ice which was buried deep below the colluvium. Finally we flew a little higher and were let out in a foggy snowstorm and had to hike up to where we thought we were supposed to go – it was intense! But the sun came out, we figurted out where we were and and we got some good samples and pics. I sent some samples to a few individuals (one of whom sent them to his colleagues) and poof! have not gotten any detailed reports back with regard to the sourcing. The Tsawataineuk, particularly Mike Willie, spearheaded and paid for the helicopter and should be credited for rediscovering this very unique site which plays an important role in their oral tradition.
My comment on xrf sourcing – great tool in theory, but the variations Nicole speaks of (different results, same day, same machine) makes comparisons between various labs through decades a BIG problem…
ai, sounds hairy to me.
Yes, Craig the guy at obsidianlabs made the same point to me about the difficulty comparing their results to the SFU results, for example. And I wonder if this problem will multiply when the portable devices of which Rudy speaks come into wide usage. I suppose on the one hand, if they can be pinned down to source then it is all comparable that way, but in terms of the inherent variability of sources and of unknowns and of the fuzzy clusters and so forth it might not be. For example, it sounds like some Edziza and some Ilgachuz obsidians are not separable cleanly despite being hundreds of km apart, which is alarming, and further incompatible sampling might only confuse this issue….
My impression is that the reason the ‘old’ SFU XRF results from the seventies cannot be compared to Craig’s lab is not because different values were obtained from the same type of machine but, rather that the early results were not quantitative measurements (i.e., ppm) but relative measures of elemental ratios (Nelson et al 1975).
As Nicole has mentioned, reflecting on the merits and drawbacks of ratios versus numbers, we may have to learn to live with some caution about ‘actual’ ppm numbers particularly if results come from different labs and/or machines. I suspect that this difference in recording conventions probably relates a larger debate about the utility and pitfalls of ‘quantitative data’ versus ‘ratio’ measures in geology and related disciplines etc.
Rudy will probably reconcile all this in his awesome sounding forthcoming phd.
Very cool to hear about the crazed helicopter ride and eventual success amidst glacial dynamism. Please please write that up somewhere and show us all pictures!
Nelson, D. E., J. M. D. Auria and R. B. Bennett
1975 Characterization of Pacific Northwest Coast Obsidian by X-Ray Fluorescence Analysis. Archaeometry 17:85-97.
Twoeyes, hypothetically, if Jim sent me some pictures and some text then I could post something about it.
That’s an interesting debate, I am sure the new machines are “better” in many ways but if they give the illusion of over-precision, and if they make legacy data unusable, then that’s an unfortunate unintended consequence….
I don’t think I mentioned this, but the red-and-black mahogany obsidian from Williston is definitely NOT Glass Buttes. It has some general similarities to some of the Edziza materials; perhaps its a little-used source from there. Darcy and Matt, are you going back there this summer?
Morley, I am pretty sure I have seen a red or orange and black obsidian from Edziza somewhere – a nodule someone collected rather than an artifact. Green too, and bluish. A lot of work yet to be done at that source.
We’ve seen lots of Edziza blue and green. I love the blue obsidian! Its from one of the main sources, Fladmark collected source material from there. I have a feeling that I saw Edziza red-and-black obsidian in his lab.
OK, this blog site is slightly addicting … promise I won’t try to hog the recent comments section 🙂
As a heads up to all, we will be launching an XRF service in the coming month – the instrument is at the border and I’m finalizing NRC certification for operation of open source X-rays (the instrument is a hand-held). I do not anticipate being able to accept samples for sourcing until July though, as there is a lot of background work to do yet, including creating new profiles for many materials. Unfortunately, the nature of signatures is somewhat particular to the instrument used and associated filters, as experienced first hand in running trials on both ‘table-top’ and portable XRF & XRDF instruments from various manufacturers. Hence some existing resource libraries may be largely useless at this early stage. I am finding that it is just easier to re-run samples then to extrapolate old results mathematically and hope you get it right. Initial services will be offered for northern obsidians, volcanic ashes, historic metals, historic ceramics, gunflints, and lead in soils (an underrated safety issue when it comes to excavating sites along highways) – there is a library of signatures readily available for us to tap into, and it is the easiest way for me to defray the costs of the subsequent research. Pricing will be competitive, and it also means that the artifacts will stay in-province. However, I’m not here to pitch the business for now … Phase 2 will be developing parallel signatures for Ty’s dacites (with his help), and assessing the viability of sourcing cherts in NE BC -NW AB – SW NWT triangle – I think it can be done, the problem is the lack of known recorded sources and the variability of cherts recovered in the region. In August 2009 we produce a map internally illustrating all the recorded ‘quarries’ in BC & AB. I’ll forward it to Quentin, maybe he’ll post it ? Should be an interesting discussion. If you’d like a copy of the map in the interim please contact me, keeping in mind that we only filtered for the term ‘quarry’ in the site records – some have been missed, I just don’t know how many.
That’s interesting you are getting one of those portable XRF as well. Sounds like Rudy is getting one too. I hope they are compatible with each other at least! I am assuming your interest in these is CRM-based, or is this a sideline in assessing samples for other projects/companies, a technical services mini-company or something?
I do wonder a bit about all these incompatible methods and the inevitable redundancy of effort. But to the extent that XRF and comparable analyses become standard and expected in CRM then it has to be a good thing on balance.
I got the map, thanks, and will reply via email.
With respect to Rudy’s instrument, it sounds like the same one I’m getting, from discussions with the manufacturer … I haven’t touched base with Rudy admittedly. The model is widely used, hence compatible with other recently developed signature sets for NW NA, and hence my ultimate choice despite not being the fanciest piece of equipment out there. It would be ideal to have at least one more small indepentent lab set up in the Province to enable the development of a communal dbase, and to push for more rigourous analysis of recovered and archived remains. As a monopoly, there could be a perception that I was setting the agenda which might disuade some from getting their materials analysed. Some collaboration is definitely in order. This sideline of mine will be run through my old company which doesn’t conduct CRM work anymore, and operate as a lab strictly for the provision of technical services (XRF is only the start …). This will hopefully distance the service from my other endeavors which admittedly include competitive consultancy.
My interest lies primarily in my own curiousity about the world around us, but its an expensive hobby so advancing technical methods in CRM is certainly a sideline. A little hard science in our CRM reports can’t hurt …
Mt. Garibaldi is in my backyard. Most of my peers don’t even realize that Mt. Garibaldi is part of a volcanic complex. The two 9,000 year-old lava flows near Mt. Price and Clinker Peak may very-well yield some obsidian. I will be checking-it-out this August and see what I come-up with, although it seems as though these lava-flows are relatively low in silica being andesitic as opposed to rhyolitic. There are always surprises wherever you venture though, and so it’s definitely worth a peek.
Hi all, just found this thread and thought I’d add my 2 cents.
First, good work Jim et al on finding the previous unknown central coast material/source. More on that in a bit.
Second, with most of this stuff in order to make anyone’s lab results with others reporting in ppm or raw concentrations is best. Calibrating techniques between different methods also needs to be spelled out well, its not at easy as 14C. Doing this allows for comparison between techniques, instruments, labs and researchers. Steven Shackley in the US SW has written extensively on this.
Three, the old SFU XRF results basically compared raw spectra results, i.e. finger prints for each source and compared those to sampled artifacts, i.e. matching to this or not. While this is a quick and easy way to get results it does not follow with what I mentioned in #2.
Four, Nch’kay (Garibaldi) source (my and may ancestors backyard!) has been found, documented and examined in my MA/PhD/publications and reports quiet extensively so it is well known if you have read my work! The outcrop is buried under more recent lava flows and may or may not pop out in other areas but I doubt it as I have surveyed all around the region, but as mentioned who knows there maybe more out there. If anyone want to hike up there and check it out let me know.
Five, as I type this Remi and I are sitting in my lab at SFU running samples form numerous NW sources (including the central coast stuff Jim et al located and collected!) and should have some very solid and interesting results.
We need to start a working group on this in order to address the numerous things discussed here…I’d be happy to help organize and keep going!
Thanks for your comment. I look forward to more results.
It’s interesting what you say about compatibility – sounds like a digital vs. analogue problem. Is there anyway to salvage the older results and make them comparable to more modern techniques?
A working group would be a great initiative especially if task number one was to ensure standardized reporting of these kinds of results. It’s obviously frustrating when independent techniques produce non-comparable results especially around here where we are behind the curve in archaeological science (in my opinion) and it would be too bad if the ball didn’t get rolling with really solid protocols.
Morley’s comment about the red/black obsidian not from Glass Buttes reminds me of the microblade core frag I found in the “ASSMAT” bags from Chinlac, in 1983 at UBC. It’s puzzled me for years since never having seen red/black from anywhere else, I had assumed it was from Glass Buttes. Thanks, Morley.
I just found this thread. Although the issue does not really impact obsidian studies – Nicole raised a really important point above. You have to be absolutely certain about the mineralogy of the rock you are studying before you try to source it. To the best of my understanding, the geological standard is now to use the SEM microprobe to visually identify crystals, phenocrysts, inclusions etc and to run many many XRF spot measurements and ICP bulk analysis. Near Infrared Spectrometers (portable, non-destructive, instant results) for geological analyses are also specfically designed for this. They work on entirely different principles, but are very accurate, and individual analyses are basically free.
Back to obsidian – NIR spectrometers get very poor signals from obsidian, but excellent signals for a very wide range of other tool stones.
Good to see this discussion.
I am very interested in a working group.
Thanks so much for the update Jesse. Great to hear about the current geological standards.
I’d be interested in the working group too Rudy.
i just read all the posts on here. i dont know if anyone is still following this but i see some of you are talking about williston area. do you mean williston lake b.c. i have found some spearheads arrowheads and knives in this area made out of obsidian and quartz some are really nice the one knife is about a foot long
Dustin, thank you for sharing this information. However, please don’t collect more of artifacts as it is not legal and it does not add to our archaeological knowledge if individually collected artifacts are not adequately documented. I suggest you consider donating your finds to a museum with as much location and documentation information as possible. If you are concerned that the find sites and artifacts at them are threatened by atv traffic, erosion, etc. I suggest you approach the local First Nation and or a professional archaeologist who can follow appropriate protocol.
The BC archaeology Branch has a helpful guide online:
Hi Dustin. You might want to get in touch with Morley at Millennia Research. They have an archaeological program running on Williston Lake and I am sure would be very interested to see what you have found and explain it’s significance and possibly its age and share some other information too. You can contact him through their website: http://millennia-research.com/
I just found an obsidian arrowhead on the the beach at Eagle Cove, on Salt Spring Island (just across from Portland Island). I’d attach a photo if I could. It’s about 1 1/2″ long brown clear obsidian with a shiny white glassy coating over most of it. Sept 4, 2016