Rockhounding in Niobrara County, WY: 57 USGS Mineral Sites (2026)

Check access before you go. Most sites listed here are old mines, quarries or prospects, and many are on private land or active mining claims. Get the landowner's permission, check the rules of the agency that manages any public land, and never enter mine workings. Locations are approximate.

Sketch map

Past ProducerProducerProspectOccurrenceStatus unknown

34 paw pins; nearby sites are grouped into one pin. Hover or tap a pin for the site name. County outline: US Census Bureau cartographic boundary file (2023). Locations approximate.

Woof’s favorite find

Silver Cliff Mine

We picked it because its USGS record mentions 2 gem or collectible minerals (Gold, Silver) and 3 of our card minerals overall. No other named site here scores as high on both counts. USGS lists it as past producer for Uranium, Silver, Radium, Gold, Copper. Minerals mentioned: Gold, Copper, Silver. Approx. location 42.762, -104.469. USGS record.

Ask first: a USGS record doesn’t mean you can visit. Find out who owns the land and get permission before collecting.

Field cards: what kind of sites?

Occurrence

The mineral was noted here, without development.

Unknown

Status not recorded.

Past Producer

Produced ore or material at some point in the past.

Prospect

Explored or test-dug, with no recorded production.

Status terms come from USGS MRDS records.

Mineral cards

Copper
Mohs 2.5–3. Native copper is soft and turns green as it weathers. Mindat
2 sites
Gold
Mohs 2.5–3. Soft, heavy and bright yellow; it doesn’t tarnish. Mindat
1 site
Silver
Mohs 2.5–3. Native silver tarnishes black. Mindat
1 site

Counts are sites whose USGS record mentions the mineral or commodity. Hardness from Mindat.

Minerals recorded here

Uranophane 4Tyuyamunite 2Chrysocolla 2Malachite 2Barite 1Hematite 1Copper 1Silver 1Chalcocite 1Azurite 1Cuprite 1Metatorbernite 1

Commodities

Uranium 54Copper 2Iron 1Silver 1Radium 1Gold 1

Sites (first 40)

Site	Commodity	Minerals recorded	Status	Approx. location
Davis Fee Land	Uranium	Barite, Tyuyamunite, Uranophane	Occurrence	43.052, -104.691
Unnamed Prospect	Copper	Chrysocolla, Malachite	Occurrence	42.868, -104.489
Silver Cliff Mine	Uranium, Silver, Radium, Gold, Copper	Copper, Silver, Chalcocite, Malachite, Azurite, Cuprite, Chrysocolla, Metatorbernite, Uranophane, Pitchblende, Clinozoisite	Past Producer	42.762, -104.469
Unidentified Prospect	Iron	Hematite	Occurrence	42.635, -104.551
Davis Fee Land	Uranium	Tyuyamunite, Uranophane	Occurrence	43.048, -104.669
Unidentified Occurrence	Uranium	Uranophane	Occurrence	43.153, -104.313
Walt Claim #2	Uranium	—	Occurrence	43.155, -104.312
Old Woman Anticline	Uranium	—	Occurrence	43.183, -104.311
Moore Claim	Uranium	—	Occurrence	43.065, -104.621
Nelson Fee Land	Uranium	—	Occurrence	42.995, -104.691
Rolph Fee Land	Uranium	—	Occurrence	43.052, -104.691
Scott Group 1-7	Uranium	—	Occurrence	43.057, -104.441
Allsup	Uranium	—	Unknown	42.863, -104.571
Bob Cat 2 Claim	Uranium	—	Occurrence	43.090, -104.608
Locality 105	Uranium	—	Occurrence	42.862, -104.633
Ran Claims	Uranium	—	Occurrence	43.012, -104.527
Happy Jack 48	Uranium	—	Occurrence	43.001, -104.533
Locality 92	Uranium	—	Occurrence	42.988, -104.696
Ace High 1 Claim	Uranium	—	Occurrence	43.096, -104.594
N. Edge of Town Cemetery	Uranium	—	Prospect	42.773, -104.451
Old Woman Anticline	Uranium	—	Unknown	43.182, -104.310
Miller 1	Uranium	—	Occurrence	42.990, -104.735
Unknow-G.Storey Prop.	Uranium	—	Occurrence	43.100, -104.321
Hornice	Uranium	—	Occurrence	43.082, -104.621
Locality #98	Uranium	—	Occurrence	42.940, -104.692
Alter	Uranium	—	Unknown	42.937, -104.491
Locality No.91	Uranium	—	Occurrence	43.009, -104.501
Lillian 4	Uranium	—	Occurrence	43.107, -104.553
Drifter	Uranium	—	Unknown	42.997, -104.608
Unknown-No.1	Uranium	—	Occurrence	43.179, -104.301
George Storey Claim	Uranium	—	Prospect	43.182, -104.310
Airborne Anomaly 3	Uranium	—	Occurrence	43.035, -104.717
Meng Property	Uranium	—	Occurrence	43.179, -104.294
Duck Claims	Uranium	—	Occurrence	43.003, -104.531
Bowers Claims	Uranium	—	Occurrence	43.001, -104.534
Happy Jack Claims	Uranium	—	Past Producer	42.997, -104.608
Locality No.86	Uranium	—	Occurrence	43.068, -104.501
Clark Group	Uranium	—	Past Producer	43.154, -104.309
Unknown-No.2	Uranium	—	Occurrence	43.172, -104.321
Rawhide Creek	—	—	Occurrence	42.625, -104.573

Fossil collections

The Paleobiology Database lists 369 fossil collection records in Niobrara County. These are research records, not public dig sites.

Nearby counties

Goshen County · Converse County · Platte County · Weston County · Campbell County

Wyoming mineral guides

Back to all Wyoming counties.

Is It Legal to Collect Rocks on Public Land? BLM, Forest Service and National Park Rules

How we built this page: we counted named sites in the USGS Mineral Resources Data System (MRDS) for this area, left out sand, gravel, crushed stone, clay pits and unnamed sites, grouped them by Census county, and linked every site to its USGS record. We did not visit these sites, and MRDS does not tell you who owns the land or whether collecting is allowed.

Source: USGS Mineral Resources Data System (MRDS). USGS ceased systematic updates to MRDS around 2011, so status and details may be out of date. Each site links to its USGS record.

Updated October 2026

Rockhounding in Niobrara County, Wyoming