The Earth's Inner Core
The inner core is the hottest part and it's a solid ball. The inner core has temperatures and pressures so great that the magma is not able to move. The temperatures are 9000 degrees F and the pressure is intense! 4.6 billion years ago, the earth was a melted ball of rocks and metals. Scientists think that the heaviest elements like iron and nickel sinked down into the inner core. So, the inner core is probably made up of gold, platinum and uranium.
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