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
----------------------
April M. Beisaw, RPA
Zooarchaeology and Taphonomy Consulting
http://www.taphonomy.com
[log in to unmask]
--- Timothy James Scarlett <[log in to unmask]> wrote:
> > << I'm curious what different procedures people
> employ to measure
> > acidity/alkalinity.
> >
> > Tim,
> > The first question is why?
> > What information are you seeking? Just as in
> archaeology, the research
> > design dictates the methods and procedures.
> > Douglas Frink
>
> Doug poses an appropriate question. (Considering
> the number of times that I
> have asked other HISTARCH authors the same question,
> the irony is also
> amusing!) I should have been more detailed in my
> original request.
>
> 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?
>
> Short story long, so to speak!
>
> I'll summarize replies for HISTARCH if individuals
> wish to reply off-list.
> Thanks,
> 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
>
*******************************************************************
> You need only two tools. WD-40 and duct tape. If it
> doesn't move and it
> should, use WD-40. If it moves and shouldn't, use
> the tape. -- Kelli
> Scarlett
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