Gold costs were about $317 per troy ounce in 2007, but these can vary widely depending on mining type and ore quality; global mine production amounted to 2,471.1 tonnes. After initial production, gold is often subsequently refined industrially by the Wohlwill process which is based on electrolysis or by the Miller process, that is chlorination in the melt. The Wohlwill process results in higher purity, but is more complex and is only applied in small-scale installations. Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cupellation, or refining methods based on the dissolution
Simple commodity production Simple commodity production Simple commodity production (also known as "petty commodity production"; the German original phrase is "") is a term coined by Frederick Engels to describe productive activities under the conditions of what Marx had called the "simple exchange" of commodities, where independent producers trade their own products. The use of the word "simple" does not refer to the nature of the producers or of their production, but to the relatively simple and straightforward exchange processes involved. Simple exchange of commodities is as old as the history of trade, insofar as it has progressed beyond barter, and occurred for