James wrote:
Thank you all for responses !! BTW, what is a "high-alkaline cleaner" ??

We use a product called Aquamix which we bought at Lowes. It is for
deep cleaning of stone or porous(sp) surfaces. It's a bit more user
friendly than the industrial types - ie: product used in a steam
cleaner for engine cleaning. I guess the blackened stone is from smoke
which is acidic and an alkaline cleaner lifts it. all i know that it
took off 60 years of sute off our fireplace brick.



--James--




Mix a solution of high-alkaline cleaner and one ounce of chlorine
bleach per gallon of warm water. . Wet the surface of the fireplace
well with the solution, but don't use so much that it runs. Dirty water
running down the face may cause hard-to-remove streaks. Then scrub with
a brush. You know it's working when the suds are black. This always
worked for us but time consuming. We use thick bristle brushes and
scotch guard pads.