Comrades,

On the subject of periostracum preservation :

Has anyone any reliable information about the long-term stability of
Glycerine? I can't imagine that in commercial form it is 100% pure (it's
extremely hard to make anything absolutely pure) - what are the prinicipal
contaminants? Is it hygroscopic (absorbs moisture) as a surface film? Does
it readily react with, for example, acids (acetic acid; formic acid etc.)
from wood, and if so what are the products?
To what extent does Glycerine preserve the cell structure in the
periostracum - well enough for microscope slide preparation?
Thinking about the longer-term implications of this preservation method, I
would be very interested to hear from anyone who has some older (20+ years)
specimens with their periostraca preserved in this way. I would also
appreciate any pointers to literature on this matter. We have a number of
abyssal molluscs here which arrived floating in jars of thick Glycerine;
their provider insisted that this was the only way to keep them from
cracking up. I suspect that as long as air is kept out, they won't suffer
at least in the short term.