What is earth's inner core made of?

The mantle under the crust is about 1,800 miles deep (2,890 km). It is composed mostly of silicate rocks rich in magnesium and iron. Intense heat causes the rocks to rise. They then cool and sink back down to the core. read more

The Earth's inner core is the Earth's innermost part. It is primarily a solid ball with a radius of about 1,220 kilometres (760 miles), which is about 70% of the Moon's radius.[1][2] It is composed of an iron–nickel alloy and some light elements. read more

The outer core is about 1,400 miles thick, and it's made mostly of a combination (called an alloy) of iron and nickel, along with small amounts of other dense elements like gold, platinum, and uranium. These metals can, of course, be found on the surface of Earth in solid form. read more