Miller process Miller process The Miller process is an industrial-scale chemical procedure used to refine gold to a high degree of purity (99.95%). It was invented by Francis Bowyer Miller ( patented 1867). This chemical process involves blowing a stream of pure chlorine gas over and through a crucible filled with molten, but impure, gold. This process purifies the gold because nearly all other elements will form chlorides before gold does, and they can then be removed as salts that are insoluble in the molten metal. When all impurities have been removed from the gold (observable by a change in flame color)
Standard & Poor's Commodity Index Standard & Poor's Commodity Index The Standard & Poor's Commodity Index (SPCI) is a commodity price index that measures the price changes in a cross section of agricultural and industrial commodities with actively traded U.S. futures contracts, stretching across five sectors - Energy, Metals, Grains, Livestock, and Fibers & Softs. Only commodities that are consumed for industrial use are included in the index. Weights in the index are determined by the dollar value of Commercial Open Interest (COI) for each component commodity, and rebalanced annually each February. Effective January 31, 2008 Standard & Poor's discontinued calculation and publication of the