I'm disappointed that after only a year my new granite coping and caulk is developing what looks like rust-colored stains. Any idea what it might be? An increasing number of stones seems to be affected. There are no overhanging trees so I don't think it would be some sort of sap. Lately I have been using acid magic to get rid of calcium deposits on the tile and grout, so would it be ok to try a diluted acid magic solution on the coping? I tried to upload a picture of it but it didn't work.
Thanks for any suggestions.