GEOLOGY

Detailed explanation-1: -Unlike the mineral-rich crust and mantle, the core is made almost entirely of metal-specifically, iron and nickel. The shorthand used for the core’s iron-nickel alloys is simply the elements’ chemical symbols-NiFe. Elements that dissolve in iron, called siderophiles, are also found in the core.

Detailed explanation-2: -Iron, nickel, and other heavy metals like gold, are what makes up the core of the earth because they are the heaviest of the metals and so sank toward the center of the earth.

Detailed explanation-3: -The Earth’s inner core is thought to consist of an iron-nickel alloy with small amounts of lighter elements.

Detailed explanation-4: -Many geologists believe that as the Earth cooled the heavier, denser materials sank to the center and the lighter materials rose to the top. Because of this, the crust is made of the lightest materials (rock-basalts and granites) and the core consists of heavy metals (nickel and iron).

Detailed explanation-5: -It is widely accepted that the Earth’s inner core formed about a billion years ago when a solid, super-hot iron nugget spontaneously began to crystallize inside a 4, 200-mile-wide ball of liquid metal at the planet’s center.