Silver mining is the resource extraction of silver by mining. Silver is found in native form very rarely as nuggets, but more usually combined with sulfur, arsenic, antimony, or chlorine and in various ores such as argentite (Ag2S), chlorargyrite (“horn silver,” AgCl), and galena (a lead ore often containing significant amounts of silver). As silver is often found in conjunction with these or alloyed with other metals such as gold, it usually must be further extracted out through amalgamation or electrolysis. Silver mining has been undertaken since early times. As silver is a precious metal often used for coins, its mining has historically often been lucrative. As with other precious metals such as gold, newly discovered deposits of silver ore have sparked silver rushes of miners seeking their fortunes. In recent centuries, large deposits were discovered and mined in the Americas, influencing the growth and development of Mexico, Andean countries such as Bolivia, Chile, and Peru, as well as Canada and the United States.