Under Spanish rule turquoise and lead were mined near Cerillos and copper was found at Santa Rita in the southwest in 1798. Artisanal mining for placer gold took place after an 1821 discovery in the Ortiz Mountains south of Santa Fe. New deposits, along with the reopened Spanish mine in Silver City prompted a boom in copper mining in the late 19th century. Placer gold mining expanded into the Sangre de Cristo Mountains and along the Rio Grande, while lead mining got underway in Las Cruces. Coal was discovered near gold and copper mines and potentially recoverable gold deposits grew more numerous as prospectors traced placer gold back to the veins where it originated.