the inner core is believed to consist primarily of a nickel-iron alloy known as NiFe: 'Ni' for nickel, and 'Fe' for ferrum or iron.[11] Because the inner core is denser (12.8 ~ 13.1)g⁄cm³[12] than pure iron or nickel, even under heavy pressures, it is believed that the core also contains enough gold, platinum and other siderophile elements that if extracted and poured onto the Earth's surface it would cover the entire Earth with a coating 0.45 m (1.5 feet) deep.[13]