Cleaning bronze fountain

We have a bronze fountain outside the entrance to the museum that
has become encrusted with mineral deposits (calcium, magnesium) from
the local water supply. We clean it with Orvus and distilled water
but that will not clean off the mineral deposits. Any ideas on how
to remove them without damaging the patina?


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                  Conservation DistList Instance 15:76
                   Distributed: Friday, May 10, 2002
                       Message Id: cdl-15-76-021
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