You can cause a drinking glass (melting point 1400C) to explode if you expose it to 100C and 0C water in quick succession. Differential heating, moisture vapori

You can cause a drinking glass (melting point 1400C) to explode if you expose it to 100C and 0C water in quick succession. Differential heating, moisture vaporizing, and expansion/contraction are larger concerns than the stone becoming lava.