Explanatory notes
… sulphate is carefully purified to remove cadmium, iron, copper, etc., and is then electrolysed to produce a very … XV : (1) Zinc‑aluminium alloys, usually with added copper or magnesium used for die‑casting, especially for … pipelines, condensers, etc., against corrosion. (2) Zinc‑copper alloys (button metal alloys), for casting, stamping, …