Abstract: A method of treating value bearing material comprising oxidized or surface oxidized mineral values includes the steps of crushing the value bearing material, contacting the crushed material! with a sulfide solution to sulfide the oxidized or surface oxidized mineral values, and adding ions of a selected base metal to the crushed value bearing material. The value bearing material may comprise oxidized or surface oxidized base metal or precious metal minerals. The crushed value bearing material is prepared as a slurry or pulp comprising from 15% to 40% solids and the remainder comprising water. The sulfide solution preferably comprises a soluble sulfidiser such as sodium hydrosulfide and the base-metal ion solution preferably comprises metal salt of base metals like copper or iron.

Abstract: A method of treating value bearing material comprising oxidised or surface oxidised mineral values includes the steps of crushing the value bearing material, contacting the crushed material! with a sulfide solution to sulfide the oxidised or surface oxidised mineral values, and adding ions of a selected base metal to the crushed value bearing material. The value bearing material may comprise oxidised or surface oxidised base metal or precious metal minerals. The crushed value bearing material is prepared as a slurry or pulp comprising from 15% to 40% solids and the remainder comprising water. The sulfide solution preferably comprises a soluble sulfidiser such as sodium hydrosulfide and the base-metal ion solution preferably comprises metal salt of base metals like copper or iron.

Abstract: A method is provided for reducing the consumption of alkaline pH modifier in a mineral separation circuit which employs sulfoxy radical-containing reagents. The method comprises the addition of a non-oxidizing gas to the mineral separation circuit prior to and/or simultaneously with the addition of the sulfoxy radical-containing reagent. The non-oxidizing gas is added in a quantity sufficient to achieve a chemical environment conducive to the flotation separation of minerals. The inventive process is suitable for a wide range of valuable minerals including sulfidic copper minerals or mixtures of sulfidic and non-sulfidic copper minerals, sulfidic iron minerals (particularly pyrite) and non-sulfidic gangue material. It is particularly suitable for sedimentary copper deposits, copper skarns, porphyry copper/molybdenum/gold deposits and super gene enrichments.

Abstract: The present invention provides a process for the recovery of base metal sulfides including chalcocite, chalcopyrite, pentlandite and platinum group metal bearing mineral ores. The process involves passing a slurry of the ore through a reagent conditioning stage wherein suitable activators, collectors, frothers and/or depressants are added, further conditioning the slurry with a non-oxidizing gas in a quantity conducive to the separation of the sulfide minerals from the remainder of the ore and subsequently subjecting the slurry to a final flotation treatment with a flotation gas having a higher oxygen content than the non-oxidizing gas. The non-oxidizing gas conditioning can be carried out prior to or after the reagent conditioning stage.

Abstract: A method of increasing both flotation selectivity and effectiveness of a sulfoxy radical-containing reagent added to a mineral separation circuit. The method involves adding a non-oxidizing gas to the mineral separation circuit prior to and/or simultaneously with the addition of the sulfoxy radical-containing reagent in a quantity sufficient to achieve a chemical environment conducive to flotation separation of minerals. The process is suitable for use with a broad range of slurries and flotation concentrates having a mixture of valuable materials including sulfidic copper minerals, sulfidic and non-sulfidic copper minerals, valuable lead and/or zinc and/or nickel minerals, sulfidic iron minerals (particularly pyrite) and non-sulfidic gangue material. It is particularly suitable for polymetallic ores containing economic values of copper and/or lead and/or zinc and/or nickel which is frequently in association with iron sulfide.