Write names of the three methods for concentration of ores.

Three methods of concentration of ores are:

(i) Concentration or centrifugation on the basis of difference of densities: This method is used when there is large difference in densities of ores and impurities.

(ii) Froth floatation method: This method is used for the concentration of ores of the metals whose ores are in sulphide form.

(iii) Magnetic separation: This method is used when either of ore or the impurity have some magnetic properties.