> ----------
> From:         Thomas E. Eichhorst[SMTP:[log in to unmask]]
> Sent:         maandag 14 juni 1999 20:39
> To:   [log in to unmask]
> Subject:      Re: holding clam valves together
>
> Andrew,
>
> Just latching on to one of your statements, namely that about pyrite
> fossils and their slow (a few decades) disappearing act.  I have an
> ammonite and several small oysters that are pyrite fossils.  I will have
> no trouble isolating them but do you have any recommendation for
> preserving them?  I had always assumed once out of the weather, they
> were here for ever.  Any ideas?
>
> Tom Eichhorst in New Mexico, USA
>
> (Of course, in a few decades, I really won't care)
>
        Dear Tom,

        In Naturalis at Leiden, The Netherlands, pyrite fosslis are kept
under silicone-oil. In order to remover all the oxygen , the tube with
fossil under the oil is vacuum pumped. After the silicone-oil has filled all
the holes of the fossil, the vacuum is teminated, the tube is closed with a
stop. They hope the fossil can be kept for years in this way. It is quite a
lot of work!
Personally I work with a plastic glue, thinned with acetone. The fossil is
emersed in the thinned glue until all air is removed. The fossil is "dried"
and can be kept for several years, but mostly not for several decades.
Martin C. Cadee, The Netherlands