It took the Spanish 30 years, after Columbus arrived in the Americas in 1492, to discover the major hoards of gold and silver that the native Americans had accumulated. In 1521, the Spanish looted Tenochtitlan, the great capital city of the Aztec Empire. After that they stormed into Central America and plundered the treasures of the Chibcha of Columbia (this was probably the original El Dorado). In 1530, they arrived in Peru and captured the Inca Empire. When the major centers of population in South America had been plundered, the Spanish turned their attention to North America.
The gold and silver that the Spanish plundered in the Americas was immediately melted and transformed into ingots, which were easier to transport by ship to Europe. They saved a few of the unusual pieces to provide the Spanish Monarchs with a view of the culture of the Americas. The chroniclers in Europe have written about the giant sun made out of gold, and the gold and silver plants, which had been taken from the garden of the Inca emperor. These and many other artifacts were melted to mint coins after they had been exhibited in front of the Spanish elite.
The Spanish (and other European powers) took steps to keep the wealth that they were getting from the colonies a secret. But a lot of information can be gleaned from Spain’s financial records of this period. Based on these records, historians have estimated that from 1492 to 1800, between 145,000 to 165,000 tons of silver was shipped. The amount of gold shipped was between 2,739 and 2,846 tons. When the Spanish ran out of rich Indian nations to conquer, they started their mining operations. From 1500 to 1800, the mines in the Americas were providing 70 percent of the world's gold output and 85 percent of silver.
Those were the times when paper money was not introduced—so the financial impact of such massive quantities of gold and silver on the European economy was several times their monetary value. The European powers became flush with wealth which they could spend on creating new infrastructure and on improving their military and naval might.