Refining of gold comprises the following sequence of operations: melting, refining, de-golding, and electrorefining. Melting gold precipitates and/or gold cathodes is required for homogenization, reliable sampling, and pyrorefining. The crucible—which contains the charge—must be able to resist the chemical action of the fluxes used (mixtures of borax, niter, and silica at varying proportions). A borax-silica-bone ash mixture is often used to cover the melt.
KeywordsMiller Process Platinum Group Metal Sodium Chlorate Precipitate Gold Monium Chloride
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