Abstract: There is described a process for the isolation of a fine mineral product from a low-grade source of the said mineral, the process comprising the following steps:(i) forming a suspension in water of the said mineral source;(ii) subjecting the suspension to grinding with a grinding medium having a specific gravity not greater than 2.0, the amount of energy dissipated in the suspension during the grinding operation being not greater than 50 kW.hrs per tonne of the dry mineral source; and(iii) isolating from the ground suspension a fine fraction of particles comprising an increased amount of the said mineral when compared with the same fraction isolated from the unground mineral source.

Abstract: There is described a process for separating from a mixture of mineral components at least one of the components. The process comprises the steps of (a) dispersing the mixture of mineral components in water so as to form an aqueous suspension containing said mixture of mineral components, (b) mixing together said aqueous suspension and a non-polar organic liquid in which there has been dissolved or suspended an anionic collector for at least one of the components of the mixture of mineral components, the volume ratio of said aqueous suspension to non-polar organic liquid being controlled and the conditions under which said aqueous suspension and non-polar organic liquid are mixed together being such that only a small amount of energy is dissipated therein in a short time in order to effect the mixing together thereof and one liquid is uniformly dispersed in the other but a stable emulsion is not formed and (c) thereafter separating, or allowing to separate, the two liquid phases.

Abstract: A process for concentrating mica in a mixture of sand and mica is disclosed, which comprises introducing the feed mixture of sand and mica into an upper part of a density separating vessel in which is provided a rising current of an aqueous medium, the velocity of the current being uniform or substantially uniform over a horizontal cross-section of the vessel and being such that all but the least buoyant particles of the mixture are held in suspension as a bed which is gently displaced upwards in the vessel by incoming feed mixture; and passing a slurry which overflows from the vessel over a screen having an aperture size in the range from 210 .mu.m to 500 .mu.m (No. 72 mesh to No. 30 mesh B.S sieve), there being retained on the screen a mixture of sand and mica having a higher percentage content of mica, as calculated in the dry state, than the feed mixture.

Abstract: A rotary magnetic separator is disclosed which includes a ferromagnetic rotor provided with a plurality of arcuate separating chambers supported at its periphery. Each separating chamber comprises an inlet for feed suspension in its bottom coupled to a pump by way of a flexible pipe, and an outlet for feed suspension in its top, there being a fluid permeable and magnetizable packing material between the inlet and outlet. Two electromagnet poles are magnetically coupled to the rotor which serves as a further pole. The rotor can be turned by a motor so as to move certain separating chambers into the vicinity of the electromagnet poles. Feed suspension can then be supplied to these separating chambers and magnetizable particles from the feed suspension may become entrained in the packing material. Subsequently the rotor can be turned back to its original position and these separating chambers can be flushed out with clean water.