probably best to respond to the sender on this:
[log in to unmask]
i know there's someone out there specialising in rock art, but can't find the
address at the moment -
> Dear Colleagues,
> We would like technical information regarding the dangers of using chalk to
> mark petroglyphs. We need arguments and a bibliography to demonstrate to
> some
> national organizations why the use of chalk is unacceptable for rock art
> research.
>
> Thank you,
>
> Guillermo Munoz
> director GIPRI
> Member IFRAO
> Aura-CAR icomos
> -----------------------------------------------------
geoff carver
http://home.t-online.de/home/gcarver/[log in to unmask]