How did the gold that we are able to mine become part of Earth?

Where to Find Gold

According to estimates, all of the gold ever mined in the history of humanity amounts to about 152,000 metric tons. This sounds like a lot, but it is only about enough to fill up 60 trailers. Scientists believe that there is still eight times more gold in and under the oceans than has ever been mined close to the planet's surface. Like the gold that is probably floating in the Earth's molten core, most of this supply of the precious metal is inaccessible or simply too expensive to mine. Interestingly, gold has been discovered on all of Earth's continents except for Antarctica. Of course, it is possible that even that continent holds some gold under all of the ice.