Water damage to postage stamps

I am posting this question for one of our researchers who is a stamp
collector.  Part of his collection was water damaged and the
coloring from the paper in his album has stained the stamps.   He
realizes that the stamps have lost their value but he would like to
know if there is some way to remove the coloring from the stamps so
that the print on the stamps is legible.  The paper that caused the
stain is the black paper that is often used in photo albums or as an
insert in plastic enclosures.  The stamps were printed in Europe in
the 1850s.   Any advice or suggestions would be greatly appreciated.

Charles Lamb

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                  Conservation DistList Instance 8:91
                   Distributed: Sunday, May 14, 1995
                        Message Id: cdl-8-91-007
                                  ***