Veronica Dultry
Veronica Dultry thanked Mountain Man's answer

Mantle or hearth? Some mantles are removable. 

If the mantle is dyed or painted concrete you can try mixing a 1/4 cup of Pine-Sol with a gallon of water and scrubbing with a rag. Let your solution soak before scrubbing.

If the mantle is not dyed or painted you could try the same solution of Pine-Sol … Read more