White bauxite is purified by: (1) Baeyer's process (2) Hoop's process ...
(1) In Hallheroult process, the electrolyte used is a molten mixture of alumina, sodium hydroxide and cryolite. (2) Lead is extracted from its chief ore by both carbon reduction and self reduction. (3) Tin is extracted from its chief ore by carbon monoxide reduction. (4) Siderite, cassiterite and argentite are carbonate ores.