One must be careful when using granite or other solid rock. They ring and they transmit energy through them very efficiently. So you would not want to use cones under a granite slab on a concrete floor. You would be transmitting the energy directly to the components.
On the other hand, the mass is an advantage. So, to get the value without transmitting vibrations the slab needs to be isolated. So for instance elastomer pucks or Vibrapods under can isolate them from small vibrations. For my amp, I use an amp stand, with vibrapods on top of it, then the granite slab and springs on top of the granite. Mass works to my advantage here.
But even better, as I use under most of my components are vibrapods on the rack shelf, then Black Diamond Racing platforms (very dense composite... really heavy), then springs on top of that, then component. This is a fairly slim profile.
For my turntable I use a custom Silent Running Audio Ohio Class vibration platform. These guys make vibration platforms for electron microscopes and other really critical applications. It had a very significant effect on my Linn, Klimax turn table. I would say this is the highest level of vibration control, Townshend platforms are also transformative for speakers.