Lead and zinc are non-ferrous metals often found together in sulfide ores. The most common lead- and zinc-containing ores are galena and sphalerite. A lead-zinc ore may also contain gold and silver, lead sulfide, zinc sulfide, iron sulfide, iron carbonate, and quartz. Lead and zinc ores are mined primarily underground in countries including China, Australia, Canada, the Unites States, and Peru. According to the U.S. Geological Survey, 13.5 million tons of zinc and an estimated 5.40 million tons of lead were mined worldwide in 2013. In the U.S. alone, the value of zinc mined in 2013, based on zinc contained in concentrate, was about $1.60 billion and the 2013 value of recoverable mined lead, based on the average North American producer price, was about $829 million. Zinc is used as a protective coating on steel and iron, while most lead is used to make lead-acid batteries. Lead and zinc can be produced pyrometallurgically or hydrometallurgically, depending on the type of ore used as a charge. In the pyrometallurgical process, ore concentrate containing lead, zinc, or both is fed, in some cases after sintering, into a primary smelter. Lead concentrations can be 50-70%, and the sulfur content of sulfidic ores is in the range of 15-20%. Zinc concentration is in the range of 40-60%, with sulfur content in sulfidic ores in the range of 26-34%. During sintering, a blast of hot air or oxygen is used to oxidize the sulfur present in the feed to sulfur dioxide (SO2). Blast furnaces are used in conventional processes for reduction and refining of lead compounds to produce lead bullion. This refining process removes any remaining nonlead materials (e.g., gold, silver, bismuth, zinc, and metal oxides such as oxides of antimony, arsenic, tin, and copper). While the gold and silver are considered to be pollutants in the refinement process, these elements can be more profitable than the primary ore elements. It is for this reason that the accurate trace analysis for silver and gold in the ore material is essential. The quickest and best method for this analysis is wavelength dispersive x-ray fluorescence (WDXRF). WDXRF technology is well established for elemental analysis of samples at various stages during mineral processing. WDXRF offers high sensitivity down to low atomic number elements, high repeatability and element selectivity. WDXRF is also favored for its wide dynamic range and ability to achieve the performance levels needed for routine industrial applications. So how do WDXRF instruments measure up? Read the analysis of silver and gold in lead and zinc ore minerals study data and analysis.