Abstract: Inorganic oxide pigments (ceramics) are prepared by mixing the starting materials in the presence of water and in the presence or absence of assistants, drying and subsequent calcining in a rotary furnace by processing the starting materials in the presence of water into a pumpable suspension having particle sizes of 50%<10 .mu.m and 100%<50 .mu.m, dewatering the suspension by spray drying it to leave porous granules, and calcining those granules>97% from 20 to 800 .mu.m in size.

Abstract: A process for the preparation of a mixed-phase pigment based on iron oxide and chromium oxide by heating a mixture of the oxides, hydroxides or oxide hydroxides of iron and of chromium at from 600.degree. to 1100.degree. C. and then comminuting the product and working it up in a conventional manner. The essential feature of the invention is that a mixture of transparent .alpha.-iron oxide having an orthorhombic bipyramidal crystal structure and a chromium(III) hydroxide, which has been applied onto the transparent iron oxide by precipitation with an alkali, preferably sodium carbonate, is heated.The pigments according to the invention give deep colorations and are readily dispersible.