Burned refractory zirconium product

Fired refractory zirconium product, whose structure a) consists of ≥ 94% by mass of ZrSiO b) a bulk density of> 3.8 g / cm c) has an open porosity of 2-25 vol .-% being d) more than half of the open porosity consists of pores having a maximum diameter is 10 microns and the pores lie within a pore size interval whose maximum value is less than or equal to 10 times the minimum value.