RockWoof
Check access before you go. Most sites listed here are old mines, quarries or prospects, and many are on private land or active mining claims. Get the landowner's permission, check the rules of the agency that manages any public land, and never enter mine workings. Locations are approximate.

Best regions by county

Ranked by the number of USGS-recorded sites, not by access or quality.

  1. San Bernardino County: 3,566 sites; most recorded: Gold, Scheelite, Chalcopyrite
  2. Calaveras County: 2,759 sites; most recorded: Gold, Pyrite, Galena
  3. El Dorado County: 2,670 sites; most recorded: Gold, Chromite, Pyrite
  4. Siskiyou County: 2,344 sites; most recorded: Gold, Chalcopyrite, Pyrite
  5. Nevada County: 2,250 sites; most recorded: Gold, Pyrite, Galena

Top minerals

  • Gold: 4,562 sites
  • Chromite: 882 sites
  • Pyrite: 728 sites
  • Chalcopyrite: 526 sites
  • Galena: 486 sites
  • Scheelite: 445 sites
  • Cinnabar: 315 sites
  • Sphalerite: 253 sites

Mineral cards

  • Gold

    Mohs 2.5–3. Soft, heavy and bright yellow; it doesn’t tarnish. Mindat

    23,565 sites

  • Quartz

    Mohs 7. Six-sided points; smoky quartz is NH’s state gem. Mindat

    4,872 sites

  • Silver

    Mohs 2.5–3. Native silver tarnishes black. Mindat

    4,579 sites

  • Copper

    Mohs 2.5–3. Native copper is soft and turns green as it weathers. Mindat

    4,116 sites

  • Pyrite

    Mohs 6–6.5. Brassy “fool’s gold,” often cubic. Mindat

    1,123 sites

  • Galena

    Mohs 2.5–2.75. Heavy, silvery lead ore that breaks into cubes. Mindat

    515 sites

  • Scheelite

    Mohs 4.5–5. Tungsten mineral that glows blue-white under shortwave UV. Mindat

    457 sites

  • Garnet

    Mohs 6.5–7.5. Usually deep red, round many-faced crystals. Mindat

    170 sites

  • Feldspar

    Mohs 6–6.5. Blocky crystals with flat cleavage faces. Mindat

    159 sites

  • Magnetite

    Mohs 5.5–6.5. Black and strongly magnetic. Mindat

    144 sites

Counts are sites whose USGS record mentions the mineral or commodity. Hardness from Mindat.

Minerals most often recorded

Gold 4562Chromite 882Pyrite 728Chalcopyrite 526Galena 486Scheelite 445Cinnabar 315Sphalerite 253Malachite 127Psilomelane 114Molybdenite 103Silver 101

Counties

CountySites
San Bernardino County3,566
Calaveras County2,759
El Dorado County2,670
Siskiyou County2,344
Nevada County2,250
Inyo County1,796
Placer County1,474
Mariposa County1,444
Trinity County1,331
Kern County1,318
Tuolumne County1,234
Sierra County1,110
Shasta County1,013
Riverside County990
Amador County941
Plumas County877
San Diego County748
Butte County748
Mono County702
Fresno County517
Madera County496
Del Norte County422
Los Angeles County409
Tulare County396
San Luis Obispo County391
Imperial County386
Lake County296
Humboldt County290
Santa Clara County245
Sonoma County245
Napa County242
Mendocino County214
San Benito County201
Alpine County175
Monterey County170
Yuba County158
Lassen County153
Stanislaus County153
Modoc County150
Alameda County148
Tehama County123
Santa Barbara County106
Ventura County101
Contra Costa County91
Sacramento County82
Colusa County70
Glenn County69
Marin County61
Merced County44
San Mateo County41
San Joaquin County39
Kings County33
Orange County32
Santa Cruz County20
Solano County12
Yolo County11
San Francisco County (fewer than 5 sites, no page)3
Sutter County (fewer than 5 sites, no page)1

Mineral guides

Related articles

How we built this page: we counted named sites in the USGS Mineral Resources Data System (MRDS) for this area, left out sand, gravel, crushed stone, clay pits and unnamed sites, grouped them by Census county, and linked every site to its USGS record. We did not visit these sites, and MRDS does not tell you who owns the land or whether collecting is allowed.

Source: USGS Mineral Resources Data System (MRDS). USGS ceased systematic updates to MRDS around 2011, so status and details may be out of date. Each site links to its USGS record.

Updated