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orion-list Radiocarbon

Tom Simms: 

>    Again, you address nothing of the handling treatment by the
>    recovery teams and the analysis people.  I've heard of some
>    cavalier treatment.
That's already been fully acknowledged; you're being repetitive, friend.  
Lab pretreatments are effective in getting out most routine contaminants
(including cigarette smoke); that is probably not the problem.  The 
issue of the handling and uncertainties concerning chemicals or oils 
applied to the scrolls is a problem.  The Zurich lab's independent dating 
of subsamples treated partially and then fully, and checking for 
discrepancies in the measurements, diagnosed contamination on 
4QTQahat (prior to chemical pretreatment).  What some may not 
appreciate--listen up Tom!--is that in their 13 other items Zurich found 
no significant discrepancies through this procedure, indicating presumably 
no contamination.  Its true this is not infallible, and an odd case of
a contaminated sample could still slip through undetected by chance,
but still, this is important information.  This Zurich information indicates
that, statistically, most of the scrolls samples are probably not 
seriously contaminated, and therefore can be expected to give 
accurate radiocarbon dates after standard lab pretreatment.  This is 
absolutely not a situation of contamination ruining all scrolls dates, 
showing the radiocarbon method is unusable, etc.  Please Tom, 
before posting again on contamination read the section in my 
article in Flint and Vanderkam where this is discussed in detail (or 
else look up the original Zurich report in Atiqot 1991 on this), and 
contact me offlist if there is anything unclear or difficult to understand.

The problem of sample contamination from unknown sources affecting 
certain Scrolls dates is a technical problem that is solvable, and I 
believe is going to be solved.  Every battery is going to learn some 
things from previous mistakes, and perhaps make new ones, to be 
critiqued and improved by the next battery.  That is the way it works.  
This is the correct procedure--do a battery, digest the results, frame 
new questions, do a battery, digest the results, frame new questions, 
do the next battery, etc.  I dearly hope this process continues on the
Dead Sea texts so long as there are unanswered, but answerable, 
questions remaining.

Greg Doudna

For private reply, e-mail to Greg Doudna <gd@teol.ku.dk>
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