The Mojave-Rosamond district is in southeastern Kern County. The gold deposits are associated with the five prominent buttes south of the town of Mojave and west and north of the town of Rosamond.
Gold was discovered in the Yellow Rover vein on Standard Hill by George Bowers in 1894, and soon afterward other discoveries were made. Activity continued until about 1910 but waned over the next 20 years. The Cactus Queen mine was discovered in 1934, and from 1931 until 1941 mining was done in the district on a major scale. The mines were shut down during World War II, but there has been some activity since. The Tropico mine is now an historical museum and a popular tourist attraction. The district is estimated to have had a total gold and silver output valued at $23 million.
Geology and Ore Deposits
The principal rocks are Tertiary rhyolite, rhyolite porphyry and quartz latite, which are underlain by Mesozoic quartz monzonite. All the ore deposits are associated with the five prominences (fig. 29), the most important of which, both in productivity and in the number of deposits, is Soledad Mountain. The ore occurs in epithermal fissure veins that occupy brecciated and sheared zones the rhyolitic rocks. The ore contains finely divided gold, with appreciable amounts of silver minerals, including cerargyrite, argentite, and smaller amounts of oustite, pyrargyrite, and electrum. Pyrite, arsenopyrite, galena, and chalcopyrite also are present. The ore shoots range from a few feet to 40 feet in thickness, and are up to 200 feet long. The veins have been developed to depths of 1000 feet. Milling ore usually averaged about 1/3 ounce of gold per ton, but some rich ore shoots were worked in the earlier mining operations
Burton-Brite-Blank, Cactus, Cactus Queen 5 million+, Double Eagle, Crescent, Elephant 200,000 to $400,000, Excelsior, Golden Queen (includes Echo and Gray Edge, Queen Ester and Silver )ueen) $10 million+, Middle Butte $150,000+, Milwaukee, Pride of Mojave, Quien Sabe, Standard roup (Desert Queen, Exposed Treasure and Yellow lover) $3.5 million, Tropico 114,000 ounces, Wegman group (Eureka, Karma and Monarch) $100,00+, Western, Whitmore, Winkler, Yellow Dog 5800+ ounces.