Photographic and photomechanical print samples needed

One of my upcoming books requires me to study as many deteriorated
photographic and photomechanical prints as possible. I am after
prints that are, for all practical purposes, worthless, except
perhaps for my purpose, which may include destructive testing
techniques.

I already have plenty of the common varieties of silver prints but I
am looking for prints made by other processes, especially *early*:
salt prints, blueprints, ambrotypes, color prints (pre 1950), gum
prints, carbon prints, woodburytypes, platinum prints, etc.

If any of you know of such prints that have not made it to the trash
can yet, contact me directly at the address above.

Luis Nadeau
Fredericton, New Brunswick, Canada

                                  ***
                  Conservation DistList Instance 9:57
                Distributed: Wednesday, January 31, 1996
                        Message Id: cdl-9-57-006
                                  ***