Diopside crystal precursor glass frit flux in production of sanitary ware and feldspathic bodies

Claim 1

In a process of forming ceramic materials into a sanitary-ware body and then firing the body to a solid form, the improvement comprising incorporating with said material a completely vitrified, clear frit containing in solution the diopside precursors, CaO, MgO and SiO 2 , precipitating crystals of diopside from said frit in situ during said firing of the body, said frit constituting from about 0.1 to 10 by weight of said body, said precipitated crystals having an average particle size less than one micron, said firing being carried out at a lower temperature than would be required in the absence of said crystals, said frit containing deflocculent oxides in a quantity sufficient to counterbalance the effect of flocculent alkaline earths present to the extent they are respectively leached upon dispersal of said frit in a ceramic slip, said frit having essentially a composition of about: ______________________________________ Wt. % ______________________________________ CaO 15 to 25 MgO 10 to 20 SiO.sub.2 35 to 50 Additive 5 to 20 ______________________________________ said additive being selected from one or more of the following in approximately the percent indicated based on the total weight of the glass: ______________________________________ K.sub.2 O 0 to 5% Na.sub.2 O 0 to 10% Li.sub.2 O 0 to 5% Al.sub.2 O.sub.3 0 to 12% ______________________________________