Tim: Thanks for bringing us up to date on the studies underway around the world. It's hard to be patient when if the science works, the resulting dating method will revolutionize archaeological studies of ceramics and the sites they are found on. I look forward to hearing about more progress, Tim





-----Original Message-----
From: scarlett <[log in to unmask]>
To: HISTARCH <[log in to unmask]>
Sent: Thu, Jan 13, 2011 7:02 am
Subject: Re: Food for Thought: A New Way to Date Old Ceramics


Hi Tim,

There are three other teams around the world working to replicate the  
initial results of Wilson et al., including two in the US and one in  
Israel.  These are those of which I am aware. The problems right now  
are not access to samples.  We are all still trying to work out some  
of the basic science around this proposed technique.  The initial  
experiments we did here at Michigan Tech were promising, really very  
promising, but much more work needs to be done before anyone can offer  
this a useful tool.

I understand the enthusiasm and interest, and I'm sure Dr. Wilson and  
her team appreciate all the emails they received offering samples.   
Everyone will have to be patient while we see if we can reach a  
consensus on lab methods, sample selection, and all the other dirty  
details.  That will take time and money to get the basic scientific  
studies finished and published.

Dr. Wilson did an interview with the RSA in the UK which they have  
posted on-line at their website:
http://www.datingceramic.manchester.ac.uk/

Cheers
Tim


On Jan 13, 2011, at 2:52 PM, Timothy K. Perttula wrote:

> There were 2 articles published on rehydroxylation as a dating  
> method in 2003 (Kinetics of Moisture Expansion in Fired Clay  
> Ceramics: A (Time)1/4 Law), in Physical Review Letters 90(12) by  
> Moira A. Wilson et al.; and 2009 (Dating fired-clay ceramics using  
> long-term power law rehydroxylation kinetics), in Proceedings of the  
> Royal Society A, by Moira A. Wilson et al..
>
>
> Sounds like great promise, but other than the few mentions of dates  
> of brick in Wilson et al. 2009, I am unaware of other ceramics-- 
> historic or prehistoric--that have been dated. I e-mailed Dr. Wilson  
> offering to provide some sherds from a prehistoric site in Texas,  
> but received no reply to my e-mail.
>
>
>
>
>
> -----Original Message-----
> From: Megan Springate <[log in to unmask]>
> To: HISTARCH <[log in to unmask]>
> Sent: Thu, Jan 13, 2011 12:10 am
> Subject: Food for Thought: A New Way to Date Old Ceramics
>
>
> Forwarded from the Public History email list.
>
> --Megan Springate.
>
> ---------------------------- Original Message  
> ----------------------------
> Subject: Food for Thought: A New Way to Date Old Ceramics
> From:    "H-Public editors" <[log in to unmask]>
> Date:    Wed, January 12, 2011 11:59 pm
> To:      [log in to unmask]
> --------------------------------------------------------------------------
>
> A New Way to Date Old Ceramics
> Marcia Goodrich
> Michigan Tech News
> http://www.mtu.edu/news/stories/2011/january/story35249.html
>
> January 10, 2011?
> If you are an archaeologist, determining when a pot was made is not
> just a matter of checking the bottom for a time stamp. Dating
> clay-based materials like ceramics recovered from archeological sites
> can be time consuming, not to mention complex and expensive.
>
> Patrick Bowen, a senior majoring in materials science and engineering,
> is refining a new way of dating ceramic artifacts that could one day
> shave thousands of dollars off the cost of doing archaeological
> research.
>
> Called rehydroxylation dating, the technique was recently developed by
> researchers at the University of Manchester and the University of
> Edinburgh. It takes advantage of ceramics? predictable tendency to
> bond chemically with water over time.
>
> ?It?s simple,? says Bowen. First, dry the sample at 105 degrees
> Celcius. This removes any dampness that the ceramic might have
> absorbed.
>
> Then, weigh the sample and put it in a furnace at 600 degrees Celsius.
> The chemically bonded water, in the form of hydroxyl groups (single
> atoms of hydrogen and oxygen bound together), forms water vapor and
> evaporates. ?When you do that, you mimic what the sample was like when
> it was originally fired,? says Bowen.
>
> Then weigh the sample again and leave it alone. Over the next several
> weeks, the ceramic will react with water in the air and gain weight.
> Plot the gain against a time constant, and the shape of the curve
> tells you the age of the ceramic. Theoretically.
>
> But it ain?t necessarily so, Bowen discovered, working with his
> advisors, Jaroslaw Drelich, an associate professor of materials
> science and engineering, and Timothy Scarlett, an associate professor
> of archaeology and anthropology. ?The dating process turns out to be
> more complicated than the literature suggests,? he says.
>
> Using shards of pottery dating from 1854 to 1888, which Scarlett
> provided from an archaeological dig in Utah, Bowen tried out the
> original dating technique at different temperatures and got
> significantly different ?ages? for the shards. He then developed a new
> equation that addresses those temperature effects, as well as the fact
> that rehydroxylation is actually a two-step process: First, water
> vapor physically penetrates the pottery. Then, it bonds chemically to
> the pottery?s constituent minerals.
>
> Bowen?s equation worked better, but not well enough to generate
> definitive dates. Humidity fluctuations affected the samples? weights,
> skewing the results. Now the research team is using new methods to
> provide constant humidity and will run additional tests over the next
> few months on various types of ceramics of different ages.
>
> They won?t only be using rare, antique pottery this time, however.
> ?This year we are using broken pieces of brick from the Houghton
> Parking Deck; it?s easier to come by,? says Bowen. ?Somebody hit it
> with their car, and when I saw the pieces, I thought, ?Oh! Sample!??
> If all goes as planned, each of those samples dated by Bowen and
> fellow researcher Tyler Botbyl, a materials science and engineering
> junior, will turn out to be about forty years old.
>
> The researchers believe their work has huge potential. ?This will be a
> new, low-cost tool allowing archaeologists to derive dates from
> objects made over 10,000 years of human history,? said Scarlett.
>
> Bowen wrote a paper on the team?s initial findings, which is being
> considered by the Journal of the American Ceramic Society. The paper
> was co-authored by fellow undergraduate Helen Ranck and both advisors.
> His work was previously supported by a McArthur Research Internship
> and a Michigan Tech Summer Undergraduate Research Fellowship. It is
> currently supported by a Michigan Space Grant Consortium Undergraduate
> Fellowship.
>
> Michigan Technological University (mtu.edu) is a leading public
> research university developing new technologies and preparing students
> to create the future for a prosperous and sustainable world. Michigan
> Tech offers more than 130 undergraduate and graduate degree programs
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>
> -- 
> H-Public
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>
>