Stains on marble

From: Eric Miller <*eric.g.miller<-at-*> Date: Wednesday, January 28, 2009 · eric.g.miller<-at-

We are currently cleaning a marble fireplace that has yellow/brown
tar stains that do not respond to our attempts at removal. Laser
cleaning works but it turns the marble yellow. (A 1999 DistList
entry affirms Synperonic N, but this is no longer available.) Any
suggestions?

Eric Miller
City and Guilds Art
School of London

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                  Conservation DistList Instance 22:43
                Distributed: Saturday, January 31, 2009
                       Message Id: cdl-22-43-029
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