At the center of the Earth is believed to be a solid inner core primarily made of iron and nickel. This solid inner core is surrounded by a liquid outer core, which is then encompassed by the solid mantle and crust.
At the center of the Earth is a solid inner core made primarily of iron and nickel. This core is estimated to have a radius of about 1220 kilometers (760 miles). Surrounding the inner core is the outer core, which is a liquid layer of molten iron and nickel. Beyond the outer core is the mantle, which is a semi-solid layer consisting of silicate rocks. Finally, on the surface of the Earth is the crust, which is the Earth's outermost solid layer.
