Thomas Watters wrote,
> We have Liguus packed in plastic jewel-boxes on cotton. The side of the
shell facing the cotton has been completely destroyed, the side facing up is
fine. The shells were packed in 1977.

Yipes. We have Tertiary shells packed with cotton stoppers in glass vials in
the 1880's to 1910's, with no apparent damage to the shells. However, the
cotton is yellowed and the vials are clouded internally. Evidently it is a
good idea to allow corrosive gasses to escape. Alternatively, it may be that
in 1977 cotton was bleached or treated with a corrosive chemical, or one
that left it acid, like acidic paper. A set of corals placed on newspaper in
the 1930's turned chalky next to the yellowing, acidic paper.

I got rid of all the newspapers, incidentally, except for the editorial page
of the Tuscaloosa News for March 9, 1934. On a single page are stories and
editorials about society's losing war on obscenity, controversies over
wire-tapping and Alfred Wegener's theory of continental drift, a dangerous
epidemic (whooping cough), and the manhunt for escaped criminal John
Dillinger. It comforts me.

Tom, were your shells maintained at constant temperature and humidity?
Paleontologists have found that pyritized fossils (fossils replaced by iron
sulfide) tend to oxidize more rapidly under varying conditions than under
conditions of high but constant humidity. Ours have been stored in a
basement for the past 40 years. Before that, in a building without air
conditioning. The environment is not ideal, but, like the world revealed in
an old newspaper, at least it doesn't change much.

Andrew K. Rindsberg
Geological Survey of Alabama

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