Deposits on painting

On a recent inspection of a gallery store, I came across a deposit
on the surface of an oil painting. Not being a specialist in this
area I wondered if anyone could hazard a guess as to the cause of
the problem. The painting is oil on canvas and the surface is
obscured in places by a white crystalline deposit. The deposit does
not easily brush away from the surface and the back and frame are
unaffected.

Juliette Baxter


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                  Conservation DistList Instance 21:9
                   Distributed: Friday, June 8, 2007
                        Message Id: cdl-21-9-045
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