Cast stone fireplace mantels are made of a non-combustible man-made stone, which is similar in appearance to limestone. These mantels can be installed either sealed or unsealed; each has a different method of cleaning and care.
The best product to use on unsealed mantels is Muriatic Acid. Wear gloves when using this substance, as it can cause irritation to the skin. Using a bottle of water with a spray attachment, wet the stone lightly and then apply the acid in accordance with the manufacturer’s instructions. Do not allow the acid to have contact with the stone for longer than 30 seconds though. Continue to spray with water until the acid has been removed.
The sealant stops the fireplace absorbing any water or dirt, so any marks or dust can be wiped off using a cloth and hot water. Normal household cleaners should be avoided, as they might react with the soot and create a stain that is even more difficult to remove.
The Importance of Regular Cleaning
The longer you leave a stain on a stone mantel, the more engrained it becomes. Whether the mantel is sealed or unsealed, clean it with a damp cloth at least once every two weeks, even if the surface does not look dirty. This will keep the stone in top condition for optimal use and enjoyment of your mantel.