Hello Conchlers. I've just caught up on 2 months of postings after 3 weeks of fieldwork in Jamaica, and a week in Florida. So this is the first in a series of replies to threads that I thought needed a bit more attention.

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Gary Rosenberg, Ph.D.                  [log in to unmask]
Academy of Natural Sciences            http://www.acnatsci.org
1900 Benjamin Franklin Parkway         Phone 215-299-1033
Philadelphia, PA 19103-1195 USA        Fax   215-299-1170


>>> Charles Sturm <[log in to unmask]> 01/06/00 11:48PM >>>
Polyurethane foams degrade, and as Jordan implies, and should not be used. polyethylene and polyester foams are safe.  They are not as compressable as polyurethanes.  Some are fairly rigid but can be cut so a shell can be placed in them.


To which I'd add, the squeeze test seems to work. Squeeze the foam between thumb and finger, then release it. If it rebounds immediately, it is probably safe. If it rebounds slowly or not at all, it is not safe and will end up sticking to and etching your specimens.

Gary