Smoky Hill River (moss agate): Moss Agate & Chalk Rockhounding in Logan County, Kansas

Updated June 2026

Smoky Hill River (moss agate) is a mapped rockhounding spot in Logan County, Kansas. Reported finds include moss agate, chalk. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Logan County
State: Kansas
Nearest road: Butterfield Overland Trail
Coordinates: 38.80191, -100.86399

Geology at Smoky Hill River (moss agate)

This spot sits on Loess, mapped as silt that formed within roughly the last 3 million years. Gravels like these concentrate whatever survives the river: agate, jasper, and other tough silica typically show up as rounded, waxy stones.

Mapped unit: Loess
Age: 3 Ma to present (Pleistocene to Holocene)
Rock types: silt
Elevation: 2,650 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 Smoky Hill River (moss agate)

Best months: September to June. Typical highs run 93°F in midsummer and 45°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, OAKLEY 19 SSW station (7 mi away), adjusted for elevation.

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 Smoky Hill River (moss agate)

Each chip 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 Smoky Hill River (moss agate).

Smoky Hill River (moss agate) FAQ

Where is Smoky Hill River (moss agate)?+

Smoky Hill River (moss agate) is in Logan County, Kansas, at 38.80191, -100.86399. Nearest road: Butterfield Overland Trail.

What rocks and minerals can you find at Smoky Hill River (moss agate)?+

Smoky Hill River (moss agate) is reported to produce Moss Agate, Chalk.

Is collecting allowed at Smoky Hill River (moss agate)?+

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 Smoky Hill River (moss agate)?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Smoky Hill River (moss agate)?+

The most comfortable months at Smoky Hill River (moss agate) are September to June.

How do I get to Smoky Hill River (moss agate)?+

Open the directions link to navigate to 38.80191, -100.86399 in Google Maps. The nearest road is Butterfield Overland Trail.

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Open Smoky Hill River (moss agate) on the map

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