Polyurethane and modern human bones

The collection I oversee has a modern fetal skeleton (26 weeks
gestation) that is a scientific donation and it is extremely
fragile, partly due to processing and partly to its immature bone
microstructure. Nevertheless, in the interest of preserving such a
hard-to-come-by comparative specimen I chose a spray-on clear
polyurethane.  My reasoning was because of the hardness achieved,
the ease of application (too fragile to paint bone by bone), and the
transparency of the coat.  I did not, however, spray all of the
bones, leaving the lower long bones uncoated in case future DNA
tests ever arise.  My questions to this listserv are:  1) are there
are any long term negative interactions with the conservation method
I have chosen, and 2) is there anything better?

Thank you.  This is the first time I have ever submitted to this
group, and only through subscribing to this group has it made me
think of such issues.

Tom Bodkin, M.A.
Forensic Anthropologist
Hamilton County Medical Examiner Office
University of Tennessee at Chattanooga
Dept. of Anthropology (Adjunct)

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                  Conservation DistList Instance 12:47
               Distributed: Wednesday, November 25, 1998
                       Message Id: cdl-12-47-008
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