Silver cyanide reaction with other anions. Some silver cyanides are luminescent. Both AgCN and KAg(CN) have been used in silver-plating solutions since at least 1840 when the Elkington brothers patented their recipe for a silver-plating solution. A typical, traditional silver-plating solution would contain KAg(CN) 15-40 gL, KCN 12-120 gL and KCO gL. Silver cyanide Silver cyanide is the chemical compound with the formula AgCN. This white solid forms upon treatment of solutions containing Ag with cyanide. This precipitation step is used in some schemes to recover silver from solution. Silver cyanide is used in silver-plating. Its structure consist of -[Ag-CN]- chains in
Silver prevent corrosion and tend to affect the lustre and colour of the alloy. Electrolytically refined pure silver plating is effective at increasing resistance to tarnishing. The usual solutions for restoring the lustre of tarnished silver are dipping baths that reduce the silver sulfide surface to metallic silver, and cleaning off the layer of tarnish with a paste; the latter approach also has the welcome side effect of polishing the silver concurrently. A simple chemical approach to removal of the sulfide tarnish is to bring silver items into contact with aluminium foil whilst immersed in water containing a conducting salt, such