There is no button to activate ions generation on the remote controller of my MediCrystal Mini Mat, how do I engage this function?

Negative ions and far-infrared rays come from the stones and inner anion generating layers, naturally, upon heat distortion created by the heating layer. 

You can make this higher or lower by adjusting the temperature. Amethyst, jade, and other crystals usually emit about 200-300 ions. 

Tourmaline ceramic, enriched with special clays and volcanic elements disks, or natural black tourmaline stones generate up to 1000-1500+ Negative Ion per cm².