World Gold Deposits
Gold has been found on every continent except Antarctica.
It is estimated that worldwide, the total amount of gold ever mined is 152,000 metric tons This is surprisingly small when you consider that this would only fill 60 tractor trailers.
World's Largest Surface Reservoir for Gold
Oceans are the greatest single reservoir of gold at Earth's surface, containing approximately eight times the total quantity of gold mined to date. However, the current cost of extracting it is more than the gold is worth.
World's Largest Deposits of Gold
The massive deposits of the Witwatersrand mines in South Africa have produced more than 40 percent of the world's total production of gold. The origin of these ancient ores--several billion years old--is controversial. Some geologists think these deposits were formed when streams deposited the gold into an ancient lake nearly three billion years ago. Over time, the gold-bearing sediments solidified into rock. Others point to evidence that after an initial placer deposit was formed, the gold was redeposited by hydrothermal fluids, like those in a hot spring.
Treasure of Five Continents
Gold has been mined from most countries on Earth. Although the mineral occurs in many different types of rock and ore deposits, the deposits themselves are surprisingly similar. For example, most gold occurs in native form--that is, pure or nearly pure--and most gold is not visibly crystalline.