AMACO CO-05 Dark MatterCosmos 05 Dark Matter is a deep, fluid glaze with shifting violet undertones and large rainbow crystals at cone 6. Crystals are smaller, and more condensed at cone 5. Apply to: Cone 04 Bisqueware Number of coats: 4 coats For best results, leave the inside or back of the form unglazed. Can be fired in a normal medium speed firing with no special cooling schedule required. To take this glaze to the next level, use a controlled cooling schedule for