In October 1850, he was on a Grass Valley hillside when he came across an outcropping of white quartz rock laced with yellow.

His find was announced by another miner, George Crandall (1825–1908), who ran down to Boston Ravine, a small settlement nearby, with the news.

He and friends constructed a crude stamp mill made out of the local forest's pine tree logs and equipped it with metal boots.

[5] Before the end of the year, thousands of people had moved to Grass Valley and neighboring Nevada City, California.

[6] A fire struck Grass Valley on September 13, 1855, destroying the entire town of over 300 wooden buildings, but it was soon rebuilt with safer materials.