After speaking with the objects conservator we employ several years
ago, we were recommended to use Soluvar varnish as the medium to apply
to objects before and after a number is put on the object. It takes
about three to four hours (depending on humidity levels) for the
varnish to dry before the number is applied. This material is soluble
in VMP Naptha and is reversible.

Joseph S. Mella
Art Curator
Vanderbilt University Fine Arts Gallery
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