Often, glaze recipes are intended for a specific firing atmosphere. Glazes like Celadon and Copper Red require a reduction atmosphere in order to achieve the intended blue/green or red color for those glazes. Other glazes like clears and whites might look the same whether they are fired in oxidation or reduction.
Some recipes like flashing slips and luster glazes are specifically designed to give special effects in wood, salt & soda, or raku firings.
