Process for preparing metal oxide granules having a particle diameter of 200 to 1500 µm, characterized in that a pyrogenic metal oxide powder selected from the group consisting of the oxides of Al, B, Ce, Cs, Er, Fe, In, Ga, Ge, Ni, Pb, Sn, Ta, Zr and/or Zn with a tamped density of 10 to 1200 g/l is compacted to slugs which are subsequently crushed and optionally classified, the slug fragments having a tamped density of 210 to 2000 g/1.