Removing graffiti from bronze

We have a cupola structure that appears to be bronze.  It might be
brass but most likely bronze based on other installations in the
building.  Some people have recently signed their names and dates on
it with what appear to be Sharpie pens.  Everything I've
investigated so far as a cleaning technique will likely remove the
patina, which would suggest we have to clean the entire structure,
rather than just where the graffiti is.

Anyone have experiece with this?  Suggestions for cleaning
procedures? Suggestions on moderate torture techniques for the
graffiti signers?

Donovan Michael Gray
Preservation Planner
State Capitol Campus
Division of Facilities
General Administration, State of Washington
360-902-0969


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                  Conservation DistList Instance 19:25
                Distributed: Thursday, November 10, 2005
                       Message Id: cdl-19-25-020
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