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. New Castle County: 9 sites
  2. Sussex County: 7 sites

Top minerals

    Mineral cards

    • Fluorite

      Mohs 4. Cubes in purple, green or yellow; many glow under UV. Mindat

      1 site

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

    Minerals most often recorded

    Counties

    CountySites
    New Castle County9
    Sussex County7

    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 USGS ceased systematic updates to MRDS around 2011, so status and details may be out of date.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