06-23-13: RichardkrebsThis is not correct. Granite is very very hard and therefore tends to pass energy straight through in both directions, it does not sink energy in of itself. Therefore what the granite sits on becomes important. For example HRS use a polymer to dampen the natural resonance their granite shelves.
My TT and Pre happen to sit on granite surface plates, surplus left overs from our machin shop. They are used, not of their flatness but their energy sinking properties.
Readers should also be aware that granite contains high levels of uranium and can be considered radioactive.
My own experience with granite is a hard edge to the sound in the upper mid lower treble - granite has a definite sonic signature related to it's natural resonance.