>I’ll give you that, no telling what will show up in any particular stone when it’s subjected to heat abuse. The stone probably won't heat up much at all, but the metal touching it will expand quite a bit, even in just the sunlight. The expanding metal will put a lot of pressure on the tight fit to the stone and it can cause the stone to crack or at least chip on the edges. Expansion joints are found all over the engineering world for that very reason.