Description: Stone Cleanse is a no scrub, no rinse cleaner that is safe and effective for removing stains caused by algae, mildew, mold, moss, and lichen from exterior surfaces without the use of hazardous chemicals (such as bleach) or the harmful effects of pressure cleaning. Stone Cleanse is perfect for use on sensitive surfaces such as monuments and sculptures, but can be used on any exterior surface, including roof, sidewalks, decks, fences, and awnings.