Zinc is a chemical element with the atomic number 30 and the symbol Zn. At room temperature, zinc is a somewhat brittle metal with a silvery-greyish look when oxidation is eliminated. It is the first element in periodic table group 12 (IIB). Zinc is chemically similar to magnesium in various ways: both metals have just one normal oxidation state (+2), and the Zn2+ and Mg2+ions are of comparable size. Zinc is the 24th most abundant element in Earth’s crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity (electrowinning).