Sounds exciting. 


Harding Polk II
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-----Original Message-----
From: Timothy Scarlett <[log in to unmask]>
To: HISTARCH <[log in to unmask]>
Sent: Mon, Jan 25, 2016 10:53 am
Subject: iron conservation

Hi Histarch,

My students, colleagues, and I just completed a small round of experiments using supercritical carbon dioxide fluid treatments to extract water from—and impregnate polymer into—corroded iron artifacts from archaeological sites. This reversible technique for drying and sealing nodules or artifacts can become a bulk/batch treatment for corroded iron, stabilizing them for storage. The process can cut treatment time from months or weeks down to hours per group of samples (orders of magnitude faster), while extending time between treatments, and without compromising artifact integrity. This can be applied to artifacts which are entirely corroded and lack any iron core or those with substantial ferrous metal remaining, and following this treatment, more patient and detailed conservation plans can be executed when desired.

This is particularly important for industrial and historical archaeology sites that produce overwhelming volumes of corroded ferrous metal. Also for brownfield and superfund sites, since the technique can be “tuned” to extract toxic compounds like arsnic, DDT, and such, without damaging artifacts from sites or any period that were exposed to contaminated groundwater or processes that contaminated them during their life-history.

As with other studies using subcritical pressures, this may be tweaked to quickly and effectively extract chlorides. The studies of this are ongoing by a group of conservators and engineers, many of these studies appear it he bibliography.

I welcome comments
Cheers,
Tim Scarlett


http://www.mtu.edu/social-sciences/research/reports/Scarlett_Caneba_Final_Report.pdf <http://www.mtu.edu/social-sciences/research/reports/Scarlett_Caneba_Final_Report.pdf>