The mat should not feel hot to the touch. Amethyst radiates heat, and the mat's surface remains warm, which is normal. When you lie on the mat, your body's cells will absorb all the heating energy. If you don’t lie down on the pad or cover it with a thick protector like the 3-D Pad or a blanket, the heat from the stones will dissipate into the air. To get the mat really hot, up to 70°C (158°F), please cover it while preheating.