What would you use to clean black soot off the front of a stone fireplace?
Stones or brick can be cleaned with trisodium phosphate (TSP), a cleaner and degreaser often used to prep walls before painting. TSP can be purchased in powdered or liquid form at the hardware store. The product is toxic if swallowed and will irritate eyes and skin—so wear gloves and goggles—but it won’t release fumes, has no lasting health effects, and is less caustic and poisonous than similarly effective products. It does contain phosphorus, however, so don’t make a habit of cleaning with it. Smoke from your fires should be going up your chimney, so if the brickwork or stone is black, there may be a problem with the fireplace itself.