Labelling soap

Does anyone know a safe way to apply a registration number to soap?
We have a 1940 soap in our collection that needs to be labelled. It
is a thick disc of plain soap with low relief decoration.

We are considering simply writing the number on a separate label or
on the storage box, but the collection managers would prefer to
apply the number directly if possible.

Joanna Morton
Conservator, Objects
Te Papa


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                  Conservation DistList Instance 14:22
                Distributed: Saturday, October 14, 2000
                       Message Id: cdl-14-22-012
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