TLC of natural resins

I'd like to try to use thin layer chromatography to do some
identification of natural resin varnish layers from a painted
English chair ca.1800. I was wondering if anyone had a solvent
system worked out which gives good separations on a given type of
TLC plate.  I expect to find things like sandarac, elemi, gum
benzoin, possibly some mastic, copal, etc.  If anyone knows of any
published material on this, I'd appreciate a reference too.  I
haven't had a chance to do a thorough literature search yet,  if
anyone could give me a good reason not to, I'd love to hear about
it.

Arlen Heginbotham
81 Forest St.
Providence, RI  02906
401-272-8626

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                  Conservation DistList Instance 12:69
                Distributed: Tuesday, February 23, 1999
                       Message Id: cdl-12-69-013
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