A mineral liberation machine comprising vertical wet grinding mill (10) for grinding coarse material comprising a cylindrical housing (14) containing a rotatable shaft (15) creating an annular channel (17) with an input feed (16) for supplying coarse material and an output feed (18) for withdrawing ground product, in which the rotatable shaft (15) is equipped with a plurality of rotor discs (20) and the cylindrical housing (14) is equipped with one or more stators or stator discs (22), the discs (20, 22) on the rotatable shaft (15) and cylindrical housing (14) are interleaved such that the ratio of the height of the housing (14) to the diameter of the housing (14) is low with the diameter to height ratio being between 0.6-1.2.

A mineral liberation machine comprising vertical wet grinding mill (10) for grinding coarse material comprising a cylindrical housing (14) containing a rotatable shaft (15) creating an annular channel (17) with an input feed (16) for supplying coarse material and an output feed (18) for withdrawing ground product, in which the rotatable shaft (15) is equipped with a plurality of rotor discs (20) and the cylindrical housing (14) is equipped with one or more stators or stator discs (22), the discs (20, 22) on the rotatable shaft (15) and cylindrical housing (14) are interleaved such that the ratio of the height of the housing (14) to the diameter of the housing (14) is low with the diameter to height ratio being between 0.6-1.2.