Really?  I thought that glass is one of the least reactive things around.
Can you be sure that the glass is the culprit?

snip
From: Andrew Grebneff <[log in to unmask]>

>Glass containers are another place where problems can occur. Over time some
>glass tubes can chemically attack shells stored within. It depends of the
>additives in the glass. I got 24 000 50x6mm testtubes at a technician's
>sale. These are great for micros, except...after several years I have found
>some specimens growing crystals. These are of two types; fine white hairs
>which can completely hide the shell, and small white cubes. I don't know
>what their compositions are or how to counter the problem, other than store
>the specimens in absolutely dry conditions (absolutely impossible for me)
>or replace the tubes with something else. Bruce Marshall says that
>specimens over say 3mm won't be affected, while smaller ones will.
>Apparently the expensive glasses are more likely to attack shells, whereas
>plastic-stoppered cheap-glass containers may not.
>Andrew
>
>
John Wolff
2640 Breezewood Dr.
Lancaster, PA 17601, U.S.A.