How Much Grog?
As a general rule, larger work and tile usually demand more openess and tooth, which is accomplished by adding “temper” to the clay. Temper is added in the form of grog (crushed fire brick), kyanite, mullite or sand. Our clay descriptions give you an idea of what to expect. Keep in mind that many people break this rule with successful results. Clay Consistency One of the most challenging task is to mix clay to the proper consistency.If you need one of house bodies at a special consistency please inquire. Special consistencies can take up to 4-6 weeks depending on the mfg. Bisque and Glaze Firing When a ceramic product is twice fired, the first firing is called the bisque, or biscuit. The second is called the glaze firing. Stoneware and percelain (to be glaze-fired to cone 6-10) should be bisque fired to cone 04, although some fire to 08-07 with good results. Low-fire bisque should be at least a cone hotter than the glaze firing. Bisque firing drives off all the water in the clay struct
