Removing ink from zinc drypoint plate

I am seeking help/suggestions for removing dried ink from zinc
printing (drypoint) plates. Plates are small. They have been soaked
in mineral spirits with no effect. I have not tried long-term
soaking in turpentine or other, weaker solution.

Bill Low


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                  Conservation DistList Instance 20:41
                 Distributed: Sunday, February 25, 2007
                       Message Id: cdl-20-41-016
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