Hamilton (west): Geode Digging in Lee County, Iowa

Updated June 2026

Hamilton (west) is a mapped rockhounding spot in Lee County, Iowa. Reported finds include geode. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Lee County
State: Iowa
Nearest road: Carroll Street
Postcode: 52632
Coordinates: 40.38365, -91.37469

Geology at Hamilton (west)

This spot sits on Meppen Limestone, Fern Glen Formation, and Burlington-Keokuk Limestone, mapped as limestone that formed roughly 360 to 330 million years ago. Limestone country like this is classic geode ground: cavities in the carbonate rock can line themselves with quartz or calcite crystals.

Mapped unit: Meppen Limestone, Fern Glen Formation, and Burlington-Keokuk Limestone
Age: 360–330 Ma (Mississippian)
Rock types: limestone
Elevation: 520 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 Hamilton (west)

Best months: March to November. Typical highs run 86°F in midsummer and 33°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, KEOKUK L&D 19 station (1 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 Hamilton (west)

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

Geode Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Hamilton (west).

Across the state line from Hamilton (west)

Hamilton (west) is close enough to the Iowa border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Hamilton (west) FAQ

Where is Hamilton (west)?+

Hamilton (west) is in Lee County, Iowa, at 40.38365, -91.37469. Nearest road: Carroll Street.

What rocks and minerals can you find at Hamilton (west)?+

Hamilton (west) is reported to produce Geode.

Is collecting allowed at Hamilton (west)?+

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. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Hamilton (west)?+

Bring a crack hammer, a chisel, safety glasses, and a bucket. Candidates are rounder and lighter than solid rock; a soil pipe cutter opens them cleaner than a flat smash.

When is the best time to visit Hamilton (west)?+

The most comfortable months at Hamilton (west) are March to November.

How do I get to Hamilton (west)?+

Open the directions link to navigate to 40.38365, -91.37469 in Google Maps. The nearest road is Carroll Street.

More rockhounding in Iowa

See all 49 Iowa spots →

Open Hamilton (west) on the map

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