Zinc metal (Zn). Atomic weight 65.38. Atomic number 30. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. It is most commonly used to prevent corrosion in iron and steel. A galvanized coating on iron or steel attracts almost all local oxidation until it completely corrodes away leaving a protective surface layer of oxide and carbonate (Zn5(OH)6(CO3)2). This is a sacrificial reaction and ingots of zinc are bolted to steel ship's hulls. It is also important in diet and health although over use can be detrimental.