Zinc is a chemical element with the atomic number 30. It's a slightly brittle metal with a shiny gray appearance when first exposed to the air, but it quickly tarnishes to a dull gray. Zinc also shares some properties with magnesium, such as their oxidation states and ion sizes.
Zinc is the 24th most abundant element in the Earth's crust, with sphalerite being the most common zinc ore. The refinement of sphalerite into pure zinc involves froth flotation and roasting of the ore, followed by electrowinning to extract the zinc.
Zinc reserves are defined as the bodies of zinc ore that are economically extracted at the time of the assessment. This definition requires geological engineers to consider factors like grade, location, quality and quantity. The total reserves of zinc ore were estimated at between 1.9 and 2.8 billion tons in 2009. The largest reserves are in Iran, but large deposits also exist in Australia, Canada and the United States.
The exploration and development of mines is an ongoing process, so the estimates of zinc reserves tend to increase over time. Furthermore, geologists can't simply extrapolate data to determine an existing mine's life expectancy. Data from the United States Geological Survey (USGS) illustrates this concept by showing that the production of refined zinc increased by 80 percent between 1990 and 2010, while the estimate of zinc reserves remained unchanged during this period.
The most ore that can be commercially mined is about 480 million tons based on the technology and practices that existed in 2009. Humans had mined about 346 million tons of zinc as of 2002, with 109 to 305 million tons currently in use.
About 13 million tons of zinc are mined each year, with only aluminum, copper, and iron having higher production totals. This figure makes zinc the fourth more commonly extracted metal, with 70 percent coming from mining and 30 percent from recycling. Nyrstar is currently the largest zinc producer in the world, which was created from a merger between Umicore in Belgium and OZ Minerals in Australia.
Zinc Production (tonnes)
|Bosnia and Herzegovina
|Republic of the Congo