1)- Wipe quartz surface with warm soapy water and a clean rag/towel. 2)- Don’t use strong acid/alkaline cleaning agents or oxidizers to clean quartz surface; neutral detergent is safe and suitable normally. You can also choose the cleaner for quartz surface specially. 3)- Avoid harsh cleaning products such as: oven/grill cleaners, dishwasher detergent, floor strippers, oil soaps, paint removers/strippers, etc. Or any product containing trichloroethane or methylene chloride.