The Earth's core is the innermost layer, subdivided into: (1) Outer core (~2,900–5,150 km depth) — liquid iron-nickel alloy responsible for generating Earth's magnetic field via the geodynamo, and (2) Inner core (~5,150–6,371 km) — solid iron-nickel under extreme pressure. The core is overlain by the mantle and then the crust. Core density is approximately 10–13 g/cm³.