The present invention relates to α-Al2O3 flakes prepared by a process comprising (1) preparation of an aqueous solution of at least one water-soluble and/or insoluble aluminum salt which optionally contains at least one sulfate compound, (2) adding a basic solution and optionally at least one dopant to the aluminum salt solution (1), (3) drying of the obtained gel, followed by calcination to obtain Al2 03 flakes and alkali salts in a molten salt, and (4) removal of the water soluble parts of the calcined molten salt obtained in step (3).
