I was hoping to get some advice about a flagstone patio that was sealed 2 years ago. Most of the sealer is doing well but there are many areas where the sealer has come completly off and took some flagstone with it. The only way I can describe the damage is it looks like the surface of the moon with it's kraters. Whatever sealer was used it seems to have eaten away at the stone itself, as deep as 1/16 th to 1/8 of an inch. This damage has given the stone an unnatural appearence and the raw stone looks brighter than the surrounding areas where the sealer still holds. Do I grind, stone ,scrape, strip , or look the other way (just kidding). If there is anyone that can help a fellow tradesman, that would mean alot. Attached are a couple of pictures.