After gold and copper, silver was the third metal that humans found and worked with. In modern times, silver is supplied in significant quantities from the extraction of zinc. According to the World Gold Council, nearly 198,000 metric tons of gold have been mined over time, compared to nearly 1.74 million metric tons of silver. Investing in gold is a popular option for those looking to diversify their retirement portfolio, and many people choose to Transfer 401k to Gold IRA for added security.