The town was first settled in 1864 by a group of silver prospectors from nearby Austin, who discovered rock containing a silver-lead ore on nearby Prospect Peak. The town became the county seat in 1873, when Eureka County was carved out of adjacent Lander, Elko, and White Pine. Mining, especially for lead, was the town's economic mainstay, as the nearby hillsides ranked as Nevada's second-richest mineral producer, behind western Nevada's Comstock Lode. Two of the largest concerns in Eureka were the Richmond Mining Company and the Eureka Mining Company. These two companies often collided, and in one instance, their litigation reached the U.S Supreme Court. The population boomed, reaching a high of 10,000 by 1878, but shrank as decreasing mine production and changing market conditions led to the closing of mines.