Why can’t I use a copper heat diffuser with my MEC pots?

Copper diffusers throw out a lot of heat and do so quite unevenly.  Usually the center could have a lot more heat than the outsides and this type of uneven and high heat could cause your pot to crack.  So avoid using a cooper diffuser with your MEC pure-clay pots and pans.  Diffusers made of cast iron, carbon steel or aluminum should work fine.  If using on glass/ceramic cook tops, we recommend this ventilated diffuser as opposed to a non-ventilated one.