Removing tar from limestone

I am posting this message on behalf of a friend who is not on the
net. I would be interested in hearing from anyone who has had
experience successfully removing roofing tar from limestone. Thanking
you in advance,

Susan L. Maltby, Conservator

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                  Conservation DistList Instance 10:6
                  Distributed: Saturday, July 6, 1996
                        Message Id: cdl-10-6-016
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