[en] After grinding to grain size of less than 15 mm the uranium ore contains grains of waste rock with uranium minerals attached to them. The uranium minerals are more brittle and can therefore be separated from waste rock by grinding-off in square grinding columns in which a 45 to 85% solid phase-containing suspension is introduced. The suspension is stirred and grains thus grind each other. The waste component is then separated from liberated minerals by flotation or hydraulic sorting. The method reduces the requirement for grinding and the cost for ore treatment. (Ha)