Osborne: Septarian Nodules Rockhounding in Osborne County, Kansas

Quick details

Access

Public area

County

Osborne County

State

Kansas

Coordinates

39.40549, -98.71510

Geology at Osborne

This spot sits on Loess, mapped as silt that formed within roughly the last 3 million years. Loose deposits like these are float-collecting ground: erosion keeps moving durable rocks and minerals into gravel bars, cutbanks, and washes.

Mapped unit

Loess

Age

3 Ma to present (Pleistocene to Holocene)

Rock types

silt

Elevation

1,580 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 Osborne

Best months: February to June. Typical highs run 93°F in midsummer and 42°F in midwinter, with winter lows near 15°F.

Climate normals: NOAA 1991-2020 monthlies, ALTON 1 W station (15 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 Osborne

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

• Septarian Nodules