Abstract: An electric furnace includes a heating element which is a hollow element made of a lanthanum chromite ceramic having an interior with two open ends in an longitudinal direction, terminal portions at the two ends, and a heat-generating portion between the terminal portions. The terminal portion has a cross-sectional area larger than that of the heat-generating portion on a plane perpendicular to the longitudinal direction. The heating element is provided with high-temperature electrodes and metallic lead wires attached to the terminal portions to generate heat in the heat-generating portion. The electric furnace further includes a heat-insulating material surrounding the heating element, and a hollow ceramic member placed in the interior of the heating element.

Abstract: A method for dispersing a pigment is disclosed, wherein the pigment is dispersed in a medium solution by using sintered zirconia beads having an average particle diameter of 40 to 192 .mu.m, a density of 5.9 g/cm.sup.3 or more, and a sphericity of 1.07 or smaller. The method is particularly useful for providing an excellent coating gloss when the medium solution is a binder for forming a paint or a coating composition or a binder for forming an ink composition.

Abstract: A shot method wherein a shot media based on zirconia composed of a sintered body of partially stabilized zirconia, of which a substantial quantity of the shot media pass through a sieve of normal sizes with apertures of 2.36 mm or less, of which the mean relative density against the theoretical density of zirconia is not less than 95%, of which the mean grain size is not more than 1.0 .mu.m, and which has a mean Vickers hardness of not less than 1,000 kgf/mm.sup.2, is shot to a work surface.