Stone Gold is a heavy-duty cleaner made to clean the toughest soils on natural stone and tile. This professional-strength liquid powers through stubborn grease and soils, preparing the surface for resealing. The water-based alkaline formula is safe on stone and will not etch surfaces. Recommended surfaces include: marble, granite, limestone, travertine, slate, sandstone, flagstone, masonry, concrete, ceramic and porcelain tile, and grout.