Ingredient Amount
Gerstley Borate 20.60
Whiting 19.60
Nepheline Syenite 15.70
EPK Kaolin 10.80
Silica 33.30
Add Amount
Copper Carbonate 1.50
Tin Oxide 1.00
Silicon Carbide 0.50


Fire to cone 6 with a medium ramp schedule. I find that it is best to set a 15-minute hold to allow some of the pinholing to close off from the off-gassed CO2 that is released as silicon carbide undergoes thermal decomposition and grows your red areas. Note that the red nanoparticle blooms will form in deep places on the clay surface, as they are most protected from surface oxidation and destruction of the copper nanoparticles. This can be taken advantage of by texturing the surface—or intentionally creating deep channels for the blooms to grow in during firing.

This recipe was shared by Ryan Coppage in the September 2021 issue of Ceramics Monthly.