Polished stone on the exterior of a commercial building can get clouded with stains over time. When stone is clean and polished, it can be the most beautiful detail of the structure. Stains occur by soap scum and caulking residue, sealer and repellant overspray, calcium and lime buildup, to name a few. Presto’s Stone Restore PS is a restorative cream that restores the finish of polished stone exterior surfaces. And it is formulated to safely and efficiently remove stains without the use of high-powered or special equipment.