Rubber stamp

In a book I am examining, there is what looks like a print from a
rubber stamp, on the flyleaf. Under a stereo microscope I see very
thin ink, with virtually no relief (i.e. not sticking up above the
page) and no impression/indentation, and no bleeding. The ink is
black. I heard that rubber stamps were invented circa 1850, but a
greater age has been suggested for this one. Does anyone have any
suggestions as to what it might be if it *is* older, or
alternatively, can I be reasonably sure (as I feel I am) that it is
simply from 1850?

m


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                  Conservation DistList Instance 16:46
                 Distributed: Friday, January 31, 2003
                       Message Id: cdl-16-46-022
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