Cleaning Galalith piano keys

I am looking for information regarding the cleaning of . The keys
have become blackened and discoloured from use. The discolouration
is in the galalith and not on the surface. I am trying to find a way
of reducing the staining of the keys. If I cannot reduce the
staining the client wishes the keys to be replaced with new plastic
keys. Apart from the discolouration the keys are in good condition
with no signs of brittleness or cracking.

Rowan Smith


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                  Conservation DistList Instance 25:6
                 Distributed: Wednesday, July 13, 2011
                        Message Id: cdl-25-6-010
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