My new Advancer® shelves are more glassy on one side than the other. Is there a “right” side to be firing on? Should I have the more glassy looking side up?

Advancer plates are fired in a controlled atmosphere designed to create an oxide or glass layer that protects the plates from the harmful effects of oxidation. Oxidation or growth of the bond between the grains of silicon carbide is the primary route of destruction in conventionally produced silicon carbide kiln shelves. Oxidation or bond growth leads to warping and pre-mature deterioration of many silicon carbide plates. It may be helpful to think of the Advancer glass layer as an “inoculation” against the harmful effects of oxidation.

Sometimes Advancer plates may look different from one side to the other due to gas patterns and minor differences in surface texture that result from the way they are fired during the manufacturing process. The oxide layer (glass) may be less glossy or even appear to be dull in some areas due to a slightly rougher underlying surface texture. Such variations are primarily cosmetic. If the glass is evident to be present on one side or portion of the plate, then it is present everywhere. This has no detrimental effect on performance in terms of oxidation because the oxide layer is present but not as visible in some areas as described above. Therefore there is no “right” side to fire on.