This site is part of the 44,000 arce [sic] Las Mariposa Land Grant purchased in 1847 by Colonel John C. Fremont for $3,000. In 1850 La Mineta, a mining camp, was established here by Sonoran miners. La Mineta was changed to Princeton in 1854 for the nearby Princeton Mine co-discoverer Prince Steptoe. The Princeton Mine produced almost 4,500,000 of gold in 1860. Carlo Marre opened a general store. In 1862 Princeton was changed to Mount Bullion because a Princeton post office existed in Colusa County. Fremont chose the name to honor his father-in-law, Senator Thomas "Old Bullion" Benton because of Benton's advocacy, the gold standard. Fremont sold his Mariposa estate in 1863. In 1886 Andrew Zinkand ran the toll road. Frank Trabucco operated a general store and was postmaster for over 50 years.