Placer mining for gold in the Ortiz Mountains was carried out by the early Spanish using Indian slave labor, but the first significant placer workings began in 1821. The underground Ortiz Mine was opened in 1822. By 1832, several gold-bearing veins had been discovered. The first gold lode mine in the West was in the Ortiz, as well as the first railroad in New Mexico. The gold separation mill was the work of Thomas Edison. But following World War I, mining costs had risen and the low grade ores and relative lack of water resulted in the last mines being closed.