Sweetwater: Sweetwater Agate Rockhounding in Fremont County, Wyoming

Updated June 2026

Sweetwater is a mapped rockhounding spot in Fremont County, Wyoming. Reported finds include sweetwater agate. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Fremont County
State: Wyoming
Nearest road: Graham Road
Coordinates: 42.56046, -108.12543

Geology at Sweetwater

This spot sits on ground mapped as Alluvial deposits 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: Alluvial deposits
Age: 3 Ma to present (Pleistocene to Holocene)
Elevation: 6,510 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 Sweetwater

Best months: April to October. Typical highs run 85°F in midsummer and 30°F in midwinter, with winter lows near 8°F.

Climate normals: NOAA 1991-2020 monthlies, JEFFREY CITY station (16 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.

State guidance last verified: April 1, 2026

BLM Wyoming
Wyoming State Geological Survey
Fossil Butte National Monument
Community submissions reviewed against published agency rules

Found at Sweetwater

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

Sweetwater Agate Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Sweetwater.

Sweetwater FAQ

Where is Sweetwater?+

Sweetwater is in Fremont County, Wyoming, at 42.56046, -108.12543. Nearest road: Graham Road.

What rocks and minerals can you find at Sweetwater?+

Sweetwater is reported to produce Sweetwater Agate.

Is collecting allowed at Sweetwater?+

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 Sweetwater?+

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 Sweetwater?+

The most comfortable months at Sweetwater are April to October.

How do I get to Sweetwater?+

Open the directions link to navigate to 42.56046, -108.12543 in Google Maps. The nearest road is Graham Road.

More rockhounding in Wyoming

See all 82 Wyoming spots →

Open Sweetwater on the map

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