Thanks all!!

Actually, I tried bleach, soaking a few of them overnight.  This did not do
anything except make some a bit transluscent.  Than I moved to Muratic acid,
CLR, hydrogen peroxide, bleach, acetone, vinegar, and boiling for 48 hours
(with and withough BIZ).

The vinegar had the best results, but a chemist contacted me and said it was
time to move towards a base.  Today I will try Lye.  I had no idea these
freshwater guys were so incredibly strong! wow!! In archaeological samples,
we find them with no periostracum.  Why is it that in nature, the
periostracum deteriorates first, but in a lab I can't get it off with acids?


-----Original Message-----
From: [log in to unmask] [mailto:[log in to unmask]]
Sent: Tuesday, April 23, 2002 5:35 AM
To: [log in to unmask]
Subject: Re: periostracum question


Did you try a stove at different temperatures. The periostracum will
than mostly crack and curle up, and will hopefully be easy to
remove. Good luck.

Marc Lavaleye