-Sn- is a chemical element with atomic number 50. Tin is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element and has, with 10 stable isotopes, the largest number of stable isotopes in the periodic table. Tin is obtained chiefly from the mineral cassiterite, where it occurs as tin dioxide, SnO2. Tin is a silvery, malleable poor metal and is not easily oxidized in the air. Tin is used to coat other metals to prevent corrosion.