This was a bounced message (error) that I am sending along to the list.
>Date: Sat, 10 Nov 2001 14:37:45 -0500
>From: Timothy James Scarlett <[log in to unmask]>
>Subject: Soil chemistry, summary
>
>A short while ago, I posted a HISTARCH query regarding soil pH measurement
>in the laboratory. As part of that request, I promised a summary post to
>the group. I've usually partitioned the messages with double lines
>(=3D=3D=3D=3D)
>while my comments are separated from each individual reply with single lines
>(----). The summary and discussion follows:
>
>My original question:
>
>Greetings everyone!
>
>I'd like to hear members' thoughts on measuring soil ph in the lab. I have
>reserved small soil samples from flotation, but I'm curious what different
>procedures people employ to measure acidity/alkalinity.
>
>Cheers,
>Tim
>
>After prompting, I expanded my original post:
>
> >> I've just completed the preliminary examination of charcoal recovered from
> >> three features associated with pottery manufacturing sites in nineteenth
> >> century Utah. I processed the soil samples with fairly common flotation
> >> techniques. These samples represent the first archaeology completed on
>such sites, and I've been finishing very broad and generalized analysis as a
> >> means of developing more detailed and satisfying research questions.
> >>
> >> I set aside soil samples from two shovel tests and one larger 1x1 meter
> >> excavation unit. The shovel tests were from kiln features, including one
> >> firebox, and from a ashy pit filled with kiln wasters. I wanted to
> examine
> >> two major points:
> >>
> >> 1. That physical remains (charcoal, and perhaps seeds and other
> >> macrofossils) will probably/will probably not be present in kiln boxes.
> >>
> >> Don't assume the affirmative on this question. Many authors reference
> that
> >> kiln boxes burned very clean, consuming all wood into ash. Also, potters
> >> cleaned them out. I wanted to see if I could recover remains from the
> >> features and that it might therefore be worth my time (and limited
> funds) to
> >> consult a paleobotanical expert.
> >>
> >> 2. That the carbonized remains reflected potter's activities that were
> >> associated with the industry/craft.
> >>
> >> One of the kilns was abandoned and left open to 'contamination' in the
> sense
> >> of my question. I want to explore how the presence of wood charcoal
> >> compares with other seeds and macrobotanical ecofacts. The
> presence/absence
> >> and proportion of different remains might help me to make a judgment
> on this
> >> issue.
> >>
> >> Not to tip my hand (on my SHA paper) but I have some interesting remains
> >> from the flotations, including lots of charcoal of different species
> of wood
> >> and seeds. I'm planning to send them out to somebody with experience with
> >> Great Basin flora. (If you know sagebrush from pinyon pine and you work
> >> cheaply, give me a call!). I THINK that I can do more research on a
> number
> >> of interesting questions that relate to the potters' technological
> decisions
> >> in manufacture.
> >>
> >> However, I have enough archaeological science training to know that
> >> understanding soil pH is one essential component to interpreting the
> >> presence-absence-frequency of different botanical ecofacts. Any
> >> archaeobotanist will ask me that question, the same way she/he might
> ask me
> >> to explain the size sieves, flotation mechanics, and collection
> methodology.
> >>
> >> In addition, I also want to know about the pH of the depositional
> >> environment because I've been trying to understand geochemical analyses of
> >> the pottery fabrics and glazes. I am concerned about the depositional
> >> environment's effects upon the pottery artifacts.
> >>
> >> GIVEN THESE POINTS, I ask a relatively simple question. I did not have a
> >> soil chemistry set in the field, since I had no budget (student loans) and
> >> no equipment loans in Utah. I'll readily acknowledge that such a kit
> would
> >> be preferable. I now have, however, access to pH and other soil chem
> >> equipment here at Michigan Tech.
> >>
> >> Has anyone out there in HISTARCH-land done soil pH testing both on
> site and
> >> vs. in the lab? Can anyone share their thoughts on the drawbacks of lab
> >> readings vs. field readings of chemistry? Does anyone have any procedural
> >> advice?
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>The replies:
>------------------
>From: "Jason J. Gonz=E1lez" <[log in to unmask]>
>Date: Mon, 29 Oct 2001 10:49:28 -0600
>To: Timothy James Scarlett <[log in to unmask]>
>Subject: Re: Fwd: Re: Soil chemistry
>
>Tim,
>
>Don't know what kind of responses you have gotten on this. You say the
>samples come from kilns. I would be incredibly surprised if the samples
>would be anything but incredibly acidic, all highly dependent on what they
>were burning. Anything organic (which is what usually gets burned organic
>derivatives) burned would leave an acidic ash. Although if you aren't sure
>about what was burned this would help tell you.
>
>I have done soil testing in the field and in the lab. It depends on the
>level of accuracy you want. Essentially the methods/procedures are the same
>in both cases, where you take the soil and throw in some chemicals to get a
>reaction. The critical part is that you then measure the color reaction.
>In the field you put the solution on acid free paper and eyeball compare it
>to a standard color set you have with you. In the lab you run the liquid
>solution through a spectrometer and get a more accurate color measurement.
>If MTU has a soil science lab and someone willing to run the tests for you I
>would do that in a second.
>
>Otherwise buying a field soil test would be appropriate as well if you are
>measuring for acidity vs neutral vs alkaline or gross comparisons. Rarely,
>have I seen an archaeological analysis that needed the accuracy of lab
>tests, although the lab tests give you better control over the size and
>variation of your samples. You can get LaMotte's soil tests from Ben
>Meadows or Forestry Supplies for relatively inexpensively.
>
>In terms of the soil samples the kind information you really want, you
>probably need to do a full element analysis. This is something you probably
>should not try to do on your own, but contact a soil lab. Anyway, a
>professional soil lab that tests primarily for agricultural purposes can get
>you the information you want. You want to know carbon components, calcium,
>sodium, magnesium, etc, - all the major nutrients and elements involved.
>You would also want to compare to a non-human impacted sample to figure out
>what is human added or human changed. Personally, I think the best way to
>go on this is to send it through a soil lab analysis and throw the kitchen
>sink at it, every test they are willing to do, do it (within budgetary
>reasons of course). A field test would probably not get you the info you
>wanted. Also, trying to self teach yourself on soil testing lab procedure
>may not be the best way either.
>
>The guy to really talk to about this is Paul Goldberg at BU whom given your
>BU connections would not be hard to get a hold of. Another person is
>Richard Terry at BYU, in the Soil Sciences Department (not an archie, but
>works with a lot of archies), whom I have talked to before. Other well
>known experts are Anthony Clark whom I only know by his work and someone
>else, whom I can't remember their name of course right now. Anyway, I hope
>this helps or it may be redundant information by now.
>----------------------
>My response:
>
>Jason provided very insightful comments. Our department at MTU has a field
>soil chemistry kit. It is a very basic kit intended for farmers, allowing
>eyeballed color examination of such traits as pH and potassium. My
>experiments all seemed to place pH at 8, with one sample perhaps actually
>being more like 8.5. The problem with my reading is that our soil kit is
>supposed to be used in a farm field and the company didn't intend their kit
>to be used by an archaeologist. The color chart only provides data up to
>and including 8. I've placed some calls on campus to other departments to
>see if I can get more accurate measurements.
>
>I like Jason's recommended analyses, taking a "broad band" exploratory
>approach to the soil chemistry in relation to the geochemistry of artifacts=
>.
>I am planning to complete this kind of study. Right now my project has no
>budget, and I am just concerned with maximizing my interpretive abilities
>within budget and time limits. One must draw lines in the sand to complete
>a dissertation, or so I've been repeatedly told...
>
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D-
>
>From: "April M. Beisaw" <[log in to unmask]>
>Date: Fri, 26 Oct 2001 06:59:57 -0700
>
>Tim,
>
>I consulted with a geologist before conducting my soil
>pH analyses in NY. The method I used consisted of
>testing the soil samples in the lab, the same day the
>soil was excavated (as moisture and temperature of
>soil influence the pH). Analysis was done using an
>Omega PHH-50 pH meter using a 50ml/50ml solution of
>soil and distilled water.
>
>Make sure you first record the temperature pH of the
>water (don't assume it is 7, this gives you a baseline
>of the pH meter). Then mix the soil and water, let the
>soil settle a bit (so as not to scratch the electrode)
>insert the electrode and wait for the reading to
>stabilize.
>
>If your soil samples have sat for a long period of
>time, the pH readings will be problematic however you
>should be able to test for variations between site
>soils with some confidence. If there is any way to
>obtain fresh samples, that would be best.
>
>April M. Beisaw, RPA
>Zooarchaeology and Taphonomy Consulting
>http://www.taphonomy.com
>[log in to unmask]
>--------------------
> >> My comments:
>
> >> April's thoughts are exactly what I was concerned about.
> >> My samples resided in whirl-pack bags for several months,
> >> and they have dried out. Given April's insights, I'm only
> >> using my pH readings as relative to one another on the site.
>
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>On 10/25/01 8:05 PM, "[log in to unmask]" <[log in to unmask]> wrote:
>
> > Tim,
> > Thank you for the clarification on the context of your question.
> >
> >
> > << I've just completed the preliminary examination of charcoal
> recovered from
> > three features associated with pottery manufacturing sites in nineteenth
> > century Utah. I processed the soil samples with fairly common flotation
> > techniques.
> >
> > As your purpose is to provide a general characterization of these "feature"
> > deposits, any pH test will prove adequate -- even the simple litmus
> test -- as
> > long as you are explicit in the report. Since you have equipment
> available, I
> > would suggest a 1:1 paste (soil to distilled, deionized H2O ). Some will
> > suggest that a salt buffered water will provide a more precise reading --
> > true, but the precision is from the perspective of plants growing in these
> > soils (which of course they are neither soils nor are plants likely to
> thrive
> > in them.) Given the age of these "feature" deposits, I would expect
> that you
> > have ample potassium salts which have not yet leached from the matrix
> -- also
> > given the location, where leaching is less a problem then here in the
> East. I
> > would expect that you would find a pH value in the range of 6.8 to 7.2.
> > Deviation beyond this range could be interesting as it might indicate glaze
> > (heavy metals) contamination.
>-----------
>A comment: Doug makes an interesting observation. The samples I processed
>came from two sites. The first set sampled from a pit feature with very,
>very ashy sandy-silt. I am not surprised that the test produced readings as
>high as 8. The other tests, however, were from wind-blown sediments that
>filled in a kiln firebox after the site was abandoned. There may have been
>a miniscule quantity of ash or charcoal in the firebox when it filled in,
>and some burrowing critters disturbed the sediments as well by introducing
>organic remains. That soil didn't contain very much organic material in the
>flot, however. Doug's thought that heavy metals contamination grabbed my
>attention. For those who've never been inside a pottery kiln, I was
>intrigued because the kiln box and the artifact chamber often run with
>melted "goop" which forms when clay bricks and artifacts are heated well
>beyond their vitrification points to a state where the clay becomes fluid
>and begins to flow. This flowing ceramic often combines with gaseous glaze
>(either salt, lead, or other formula) and takes the appearance of obsidian
>or slag. Potters are forced to tear out the bricks lining the inside of a
>kiln as they melt and degrade or the entire kiln will collapse. These soils
>were in direct contact with this "goop" in the firebox and in the artifact
>chamber. Possible chemical interaction between the soil and the kiln
>structure creates all kinds of problematic interpretive issues!
>-------
> > As for field testing, a simple portable pH meter works just fine (see
> Forestry
> > Supply or Ben Meadows catalogues) -- costs under $50, accuracy +/- 0.2.
> >
> > You should keep in mind that field conditions will result in different
> > readings than air dried samples -- has to do with the living and active
> > bacteria vs the dormant bacteria.
>----------
>My comment: problem already mentioned above. Points to my need to take
>field measurements next time so I can make comparisons.
>-----------
> >
> > One other question that need be asked as these subsamples are from you
> > flotation sample -- were the samples treated with just water (distilled and
> > deionized -- i/e/ neutral to pH) or with deflocculants (e.g.,
> zinc). This may
> > bias your pH readings.
>---------
>My comment: I anticipated this particular issue and simply held back about
>50-100 milliliters of soil from each floatation for chemical examination.
>--------
> >
> > As an after thought, you might want to contextualize the soil pH values
> with
> > total organic carbon, and total oxidizable carbon values. The
> concentration
> > and nature (humus, inertinite, lignite, vitrinite) of the organic
> carbon will
> > directly influence the soil microbial population and their influence on pH.
> >
> > I think this covers most of your questions. If not, please feel free
> to send
> > more.
> >
> > Douglas
>-------
>My comment:
>
>At this stage, I have not tested the carbon level of the soils. As with
>Jason's comment, this must be something that I can plan for in future digs
>on the pottery sites. Good, substantial thoughts.
>
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>From: [log in to unmask]
>Reply-To: [log in to unmask]
>Date: Sun, 04 Nov 2001 20:49:24 GMT
>To: [log in to unmask]
>Subject: Re: Soil chemistry
>
>A couple of years ago, I did the type of pH analysis in the lab that you
>indicated that you would like to do, with the advice of the soil scientist
>on our staff (Chugach National Forest). My goal was to quantify differences
>and similarities in two sites from about the same time period and ostensibly
>similar ecological situations, but which turned up great differences in
>types and quantities of artifacts and faunal remains. We had been doing
>testing in the field and did not have a soil analysis kit with us.
>
>We proceeded by simply adding commercially available pH neutral water to the
>soil samples (using measured amounts of each), and measuring the pH of the
>resulting concoction. The results all appeared to make reasonable sense,
>and were consistent with the type of material evidence that we recovered
>from the sites.
>--------
> >> My comment:
> >> Did you know that Evian is pH balanced? I doubt the company had
> scientific
> >> use in mind when then put that on their label! I tested it, and it
> was true
> >> (for my bottle at least)
>----------
>If you'd like to have a copy of the resulting publication, and the short
>in-house paper that describes techniques and results, please email me at my
>office address: <[log in to unmask]>.
>
>Linda Finn Yarborough, Ph.D.
>Chugach National Forest Archaeologist
>Anchorage, Alaska=20
>907-271-2511
>
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>Summary:
>I have opened up a can of worms on this issue, but I think the next research
>design I write will be much better because of this analysis. I've begun to
>explore the literature on materials science and soil chemistry to try to
>learn what effect, if any, soil chemistry will have on trace-element
>analysis. I am aware of the assumptions made, but since industrial/historic
>technologies are different from pre/non-industrial manufacture, I'm always
>curious to reconsider those assumptions. I'm currently working on a
>proposal with Jeff Speakman to examine the effect of high-temperature firing
>on volatile elements.
>
>As I understand the scholars who replied to my request, the following themes
>are important in my future work on soil chemistry:
>
>1. Collect and compare field data with lab analysis of soil samples.
>
>2. Stress the inter-related nature of any given soils chemical profile,
>rather than treating one factor in isolation (to simplify: calcium will
>influence carbon will influence pH will influence bacteria, and all
>vice-versa)
>
>3. I must treat the relationship between soil chemistry (depositional
>environment) and artifact chemistry (trace-elements) as a problematic issue.
>At this stage of my analysis, given my current trace-element research
>questions, I can ignore the depositional soil chemistry in the same way I'm
>ignoring the chemistry of the raw clays. As I move to my next set of
>research questions, that will become a much more complex relationship. If
>you have more detailed questions or commentary about trace analysis, soil
>chemistry, or pottery production, come see my SHA paper in Mobile!
>(SHAMELESS hyper-media plug!) I'd really enjoy talking these issues over in
>the hotel bar after the session.
>
>I would provide a bibliography of resources mentioned, but none were. There
>is a vast literature on soil science and archaeology, and students pursuing
>this information will find references readily. I'd be happy to share with
>anyone interested, just contact me off list.
>
>I also hope that my summary will prompt others to post such follow-up to the
>list. We've seen a few examples of this in the past, and I would like to
>see more. When someone posts a follow-up summary, it makes me feel less
>like a 'research tool' when offering help to other researchers.
>
>Cheers to all,
>Tim
>
>*******************************************************************
>Timothy James Scarlett
>Incipient Assistant Professor of Archaeology
>Program in Industrial History and Archaeology
>Department of Social Sciences
>Michigan Technological University
>1400 Townsend Drive
>Houghton, Michigan 49931-1295 USA
>Tel (906) 487-2113 Fax (906) 487-2468 Internet [log in to unmask]
>MTU Website: www.industrialarchaeology.net
>SHA Website: www.sha.org SIA Website: www.sia-web.org
>*******************************************************************
>Time and Place, in mind and in matter, are the archaeologist's bailiwick.
>-- Anne Yentsch
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