Identifying substance on furniture

I have had an inquiry from the public regarding a blue powdery
substance (not mould) found in a piece of furniture originally from
Holland.  It has been suggested to the owner that it may be some
sort of insecticide. Does anyone from Europe have any experience or
information with such a substance?

Linda Berko, Conservator
PEI Museum and Heritage Foundation
Charlottetown, PEI

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                  Conservation DistList Instance 13:17
                 Distributed: Thursday, August 26, 1999
                       Message Id: cdl-13-17-008
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