More than 99 percent of Earth's gold sank to the center of our planet billions of years ago when the surface was still a sea of molten lava.
Gold is an iron-loving element and was therefore pulled towards the Earth's iron rich core.
According to Australian geologist, Bernard Wood, there is so much gold in Earth's core that it could coat the planet in 1.5 feet of the precious metal!
The Earth was formed when a series of smaller planetesimals crashed together over the course of 30 million to 40 million years.
Wood calculated how much gold should be present in the planet's crust by comparing the crust's composition to that of meteorites similar to the planetesimals. He concluded that the crust was depleted of gold.
Wood believes that, if meteorites did not deposit gold on Earth's surface after it had cooled down, gold would have been even rarer and more expensive than it is today.
Apparently all the gold ever mined and still being mined today, comes from meteorites that have hit the earth's crust since it cooled. Once inside the crust, geological forces and processes deposited it in places where we can find and extract it.
