Treasure Hunting in California

From Gold Rush ghost camps to mission-era silver, California has the highest documented lost-cache density on the West Coast.

Top California treasure regions: Mother Lode (Sierra foothills); Mount Diablo region; Death Valley fringes; San Joaquin missions.

Famous documented cases in California: Lost Cement Mine; Mojave gold camp caches; Mission silver caches; Gold Rush ghost-camp caches.

Lost Cement Mine (1857, status: unrecovered): Two German prospectors in 1857 found a reddish cement-like outcrop laced with gold near Mammoth Lakes, CA. They could never relocate it. Mark Twain documented the search craze in "Roughing It." Where: Mammoth Lakes / Mono Craters area, California. Land rules: Inyo NF and BLM. Recreational prospecting permitted outside designated wilderness.

Terrain in California: Sierra granite, Mojave desert, coastal range. LiDAR coverage is excellent statewide.

Best seasons for field work in California: October–May for desert and foothills. High Sierra is July–September.

Is metal detecting legal in California? California has no single statewide state-park rule. Each park unit decides for itself, and many historic units ban detectors outright. Most legal detecting in California happens on public beaches that allow it, on BLM desert land, and on private property with permission.

California state parks are managed by California State Parks (https://www.parks.ca.gov/); check its rules before detecting in any state park.