I have a limestone hearth on my fireplace. It has stains from ashes and sap. How can I clean it?
Re: Cleaning Limestone
This website might help.
If your limestone is truly raw, natural and in good shape, you could try sulfamic acid. It comes in a small tub from a hardware store and is used to clean grout and cement from certain unglazed tile surfaces. It literally is an acid that attacks lime and will eat away at the stone. Be VERY careful if you try this!!! Don't damage your stone, try it in a very small area and if you decide to continue, work in small patches at a time. Rinse with plenty of fresh water to keep the acid form continuing to eat at your stone. Not sure what you're delaing with, and this might not be a great option depending! Would definitely try other things first - although I'm not sure what else might work.