Earth's solid iron core formed a BILLION years ago and is still growing

Earth's inner core - Wikipedia

Earth's Core Spins Faster than Earth

Do we really know how Earth's inner core formed? The Daily The Daily

Earth's solid iron core formed a BILLION years ago and is still growing

The center of the Earth is an iron ball with a radius of 650 kilometers, Science

How Earth's cooling molten core could destroy the planet - BBC Science Focus Magazine

New region discovered at Earth's center — Harvard Gazette

Genes from Mota Cave skeleton supports the theory of a Eurasian migration into Africa

A New Power Source for Earth's Dynamo

Asal Usul Bahan Tambang di Muka Bumi, by HMT-ITB

Strange behaviour of Earth's core reveals a mystery inside our planet - The Weather Network