In the weathering process it loses its alkaline content through decomposition and becomes china clay. Potash, lithium and soda feldspars are used in ceramic glazes and clay bodies. A potash spar, low in impurities, well suited for white ceramic glazes and porcelain clay bodies. A widely used eastern U.S. soda spar.
Fireclays are yellow or gray in color but fire to an off-white to burnt tan color.
FRIT 3134 Calcium borate source used with other frits for low cost pottery glazes from Cone 06 to Cone 01. Very fluid, clear Cone 06 frit. Very low coefficient of expansion. Crackle frit, clear and used from Cone 06 to Cone 03. Can be used alone or as an additive to ceramic glaze.