You will probably need to poultice the stain with a ferrous and copper stain remover.  The one we have used is made by Prosoco.  You might need multiple applications if it initially lightens. President Mobile: 309.251.3192 Email: joyce@thepersonaltouchsolution.com Web: www.thepersonaltouchsolution.com       -------- Original Message -------- Subject: Copper stains From: Mike Marsoun <outerislandstonecare@gmail.com> Date: Thu, October 12, 2017 2:55 pm To: Stone Care Central Discussion Group <sccpartners@stoneandtilepros.simplelists.com> On a job with extensive copper patina staining that has been set in by acid rain....seems similar to an acid stain which does not come out of limestone. I tried my usual go to which works fine if it is surface but it did not budge. Any ideas? Visit list archives, subscribe, unsubscribe or change your subscription preferences: http://stoneandtilepros.simplelists.com/sccpartners Start a new conversation (thread): sccpartners@stoneandtilepros.simplelists.com Sent from my iPhone

 
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