Wax

Craig Deller <craig1708 [at] aol__com> writes

>I was recently asked about what appears to be mold growing on wax.
>...
>The owner has observed (I have not) a whitish material that forms on
>the tops of the "fruit" and can only describe it as a mold.  They
>have also said that by placing moth balls in the case the "mold"
>seems to disappear.

In regard to the "moldy" wax query, what he is probably seeing is a
phenomenon which is most commonly seen (in real life) in chocolate.
Ellen Pearlstein's article "Fatty bloom on wood sculpture from
Mali", [SIC 31 #2 1986]  explains the basic chemistry.
I have seen what looks like crystallization on crayons, wax fish
models, and on a variety of West African wooden sculpture.  The
reason that the moth balls got rid of it was that PDB is a solvent.
The fumes undoubtedly re-dissolved the wax and allowed it to
recrystallize in smaller crystals.  When this phenomenon occurs on
wooden objects, the white crystalline bloom goes away temporarily if
the crystals are dissolved, but this is not a permanent solution.

B. Appelbaum

                                  ***
                  Conservation DistList Instance 10:4
                   Distributed: Friday, June 28, 1996
                        Message Id: cdl-10-4-002
                                  ***