For thousands of years and across many cultures, amethyst has been thought to calm and clear the mind. We have no direct mechanism to explain this effect. Nevertheless, most people report an improved mood and less anxiety after a BioMat treatment. Amethyst also has a low specific heat and so it cannot store heat very well. It must shed excess heat in the form of infrared light. Other infrared devices use carbon or ceramic “lamps,” which are less efficient, producing light with shorter wavelengths and lower intensity.