Q. When we had our new slate hearth put in a few years ago we also had our living room plastered the following day. The plasterer did not put any protective dust sheets down which resulted in our beautiful new hearth being stained with plaster solution. It’s really ruined the whole look of our new hearth and wood burner. Is there anything that I can do to draw out the stain? I’ve looked everywhere online to try and find a solution but so far haven’t found any help anywhere else. We live in Northern Ireland! 

A. Thanks for contacting us with your question. We are always happy to provide instructions on how to remove stains from natural stone. First, try cleaning the slate with a soft scrub brush and a solution of dish soap and water. If the plaster residue loosens up at all, keep cleaning until it is completely removed. If it does not loosen up, then try the poulticing method. A poultice is an absorbent material applied to the surface of natural stone to draw out a stain. For the type of stain you described, the most appropriate poultice ingredients would be a tablespoon of Dawn dish soap per cup of flour and enough water to create a paste with the consistency of peanut butter. Visit our Stain Management App for detailed instructions on the poultice method, including a how-to video. If the poultice loosens the plaster residue, try cleaning the slate with a soft scrub brush and a solution of dish soap and water again. You may need to reapply the poultice and clean the stone several times to achieve the desired results. Once the stone is clean, rinse with distilled water and buff dry with a soft cloth. For further assistance, contact your stone restoration professional. To find a Certified SurpHaces PRO Partner in your area contact us.