Old Mines: Barite & Calcite Rockhounding in Washington County, Missouri
- Minerals reported
- 9
- Elevation
- 810 ft
- Best months
- February to December
Old Mines is a mapped rockhounding spot in Washington County, Missouri. Reported finds include barite, calcite, galena, goethite, malachite, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.
Plan your visit
Generally open to casual rockhounding
- County
- Washington County
- State
- Missouri
- Nearest road
- MO 21;MO 47
- Postcode
- 63630
- Coordinates
- 38.01515, -90.75614
Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.
Land & collecting status
Generally open to casual rockhounding
Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.
Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.
Best time to visit Old Mines
Comfortable months (45 to 90°F highs)
Best months: February to December. Typical highs run 87°F in midsummer and 41°F in midwinter, with winter lows near 23°F.
Climate normals: NOAA 1991-2020 monthlies, POTOSI 4 SW station (9 mi away), adjusted for elevation.
Geology at Old Mines
This spot sits on Eminence Dolomite, Potosi Dolomite, mapped as dolostone that formed roughly 495 to 485 million years ago. Carbonate rock like this dissolves and weathers readily, so fresh road cuts, quarries, and creek exposures are typically the most productive ground.
- Mapped unit
- Eminence Dolomite, Potosi Dolomite
- Age
- 495–485 Ma (Furongian)
- Rock types
- dolostone
- Elevation
- 810 ft
Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.
Today's weather
Is today a good day to go?
The app shows live weather, recent rain, and a daily rockhounding score for Old Mines.
Get the appSources & verification
Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.
- Missouri Geological Survey
- Mark Twain National Forest
- Missouri State Parks rules
- Community submissions reviewed against published agency rules
Found at Old Mines
Each name opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.
Nearby rockhounding spots
Other rockhounding spots within driving distance of Old Mines.
- Haunted Ridge RocksWashington County, Missouri · 4 mi away
- Hawks Bluff Farm Rocks and DrusyWashington County, Missouri · 6 mi away
- St. Francois CountySaint Francois County, Missouri · 15 mi awayBarite, Goethite, Pyrite
- De SotoJefferson County, Missouri · 15 mi awayFluorescent Calcite
- PalmerWashington County, Missouri · 16 mi awayAnglesite, Calcite, Cerussite
- Hinch Copper MineCrawford County, Missouri · 21 mi awayCopper, Cuprite, Limonite
- Saint ClairFranklin County, Missouri · 22 mi awayAnglesite, Galena, Barite
- Bleeding Hill MineCrawford County, Missouri · 22 mi awayCopper, Cuprite, Goethite
Across the state line from Old Mines
Old Mines is close enough to the Missouri border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.
Old Mines FAQ
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More rockhounding in Missouri
See all 93 Missouri spots →
Open Old Mines on the map
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