Bluestone slate is a beautiful natural material, but only when it's clean. Bluestone slate installed on a hearth or other frequently soiled area should be cleaned regularly to keep it looking its best. Bluestone is a member of the siliceous stone family and known for its durability. Repeated cleaning with the wrong product, however, can dull the shine on your bluestone or leave streaks behind. For the best results, only clean your hearth with a pH balanced cleaner prescribed for use on stone.
Sweep away any ash or debris that has collected on the surface of the hearth.
Mix stone cleaner and water in your bucket according to the stone cleaner's instructions. Usually, a few drops of cleaner per quart of water is a sufficient amount. Do not exceed the recommended amount of cleaner. An excessive amount of cleaner may leave buildup or streaks behind.
Dip a soft cloth in the cleansing solution and gently scrub the bluestone hearth using a circular motion.
Rinse your soft cloth, empty the bucket and fill it with clean water. Rinse the hearth with your clean cloth until all traces of the soap are gone. Change the water frequently to keep it clean and free of the wiped-up soap residue.