For firing metal clay Meteor and Art Clay, we need coconut charcoal. It’s a plant activated charcoal obtained by carbonising coconut shells. 100% natural product from thermal steam activation. Guaranteed acid-free (to prevent damaging the durability of high-temperature kilns). Particle size 1.2-2 mm. Charcoal can be used repeatedly. It gradually diminishes and needs to be replenished little by little. It’s fired in a small steel closed container.