Stone Scrub is a unique non-acidic, non-toxic compound that safely removes hard water and mineral deposits from stone and glass surfaces. Combines organic cleaning agents and a very soft abrasive to gently remover hard water deposits, soap scum and grime from polished stone and glass without harming or scratching the surface. Excellent for granite countertops, travertine showers, glass shower doors and glass shower enclosures. Will not harm faucets, fixtures or metal framing. Non-toxic and environmentally friendly. Free of any scents, perfumes or dyes. Can be used by hand or with a low speed buffing machine.