Lincoln: Chalcedony & Chert Rockhounding in Benton County, Missouri

Plan your visit

Generally open to casual rockhounding

County

Benton County

State

Missouri

Nearest road

Benton County Northeast 281

Coordinates

38.38301, -93.23182

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.

Access note: Mozarkite floats out into road ditches, gravel shoulders, and creek gravels around Lincoln, and weathered cobbles can be picked up from public road right-of-way along routes such as Highway 7. Surface collecting by hand is the norm; bring a crack hammer to test interiors since weathered exteriors look dull. Many surrounding fields are private, so stay on public right-of-way or get landowner permission, and avoid any posted Missouri Department of Conservation land, where rock collecting is prohibited under the Wildlife Code.

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 Lincoln

Comfortable months (45 to 90°F highs)

Best months: March to November. Typical highs run 88°F in midsummer and 39°F in midwinter, with winter lows near 20°F.

Climate normals: NOAA 1991-2020 monthlies, COLE CAMP 3NW station (7 mi away), adjusted for elevation.

Geology at Lincoln

This spot sits on Smithville Dolomite, Powell Dolomite, Cotter Dolomite, Jefferson City Dolomite, mapped as dolostone that formed roughly 485 to 470 million years ago. Chert and agate nodules typically form inside carbonate rock like this and weather out as tough, waxy lumps in soils and creek beds.

Mapped unit

Smithville Dolomite, Powell Dolomite, Cotter Dolomite, Jefferson City Dolomite

Age

485–470 Ma (Early Ordovician)

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.

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.

• Missouri Geological Survey
• Mark Twain National Forest
• Missouri State Parks rules
• Community submissions reviewed against published agency rules