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Re: orion Chrisso Boulis on C14 Dating
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Failing a contribution from a radiocarbon professional, it may be said
about contamination from cigarette smoke that the latter consists of
particulate matter in air suspension. It is actually relatively easy to
clean from the surfaces it adheres to by ordinary cleaning techniques. In
saying this, I do not mean to dismiss the seriousness of contamination by
cigarette smoke. But most reputable radiocarbon labs have no problems
dealing with it.
Castor oil will *not* result in a uniform offset of the dates of the
scrolls affected, as the documents were hardly bathed in the stuff; rather,
it will have been applied patchily by brush to those sections deemed in
need of cleaning or which were otherwise difficult to read, according to
the testimony of the scholars involved. As an oil, it was able to seep into
the unsealed pores between the collagen helixes in the parchment. (And
those pores themselves will have been either well or indifferently sealed
off, depending on how well they had been abraded with pumice stone in
antiquity). Hence getting it out is a task on a different order from
washing off particulate matter clinging to the surfaces. And one of the
risks involved here is that any bath that is strong enough to dissolve
castor oil may result in the gelatinisation of the sample to be tested. It
is too early to tell, as Kaare Lund Rasmussenīs testing is far from
complete, but it could well develop that castor oil *cannot* be effectively
removed from samples well enough to permit their reliable radiocarbon
analysis.
Fred Cryer