Fox City: Geode Digging in Clark County, Missouri

Quick details

Access

Public area

County

Clark County

State

Missouri

Nearest road

County Road 180

Coordinates

40.42617, -91.62929

Geology at Fox City

This spot sits on ground mapped as limestone that formed roughly 360 to 325 million years ago. Limestone country like this is classic geode ground: cavities in the carbonate rock can line themselves with quartz or calcite crystals.

Age

360–325 Ma (Mississippian)

Rock types

limestone

Elevation

590 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.

Best time to visit Fox City

Best months: March to November. Typical highs run 85°F in midsummer and 33°F in midwinter, with winter lows near 16°F.

Climate normals: NOAA 1991-2020 monthlies, KEOKUK L&D 19 station (14 mi away).

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.

Sources & 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.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Fox City

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

• GeodeEncyclopedia →
• CalciteEncyclopedia →