RockWoof
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

San Miguel Mine (Producer)Twin Mountain Rock Quarry (Producer)Folsom Area (Occurrence)Peacock Canyon Prospects (Past Producer)Black Mesa Prospect (Past Producer)
Past ProducerProducerProspectOccurrenceStatus unknown
5 paw pins, one per site. Hover or tap a pin for the site name. County outline: US Census Bureau cartographic boundary file (2023). Locations approximate.

Woof’s favorite find

Black Mesa Prospect

We picked it because its USGS record mentions 1 gem or collectible mineral (Silver) and 2 of our card minerals overall. That ties with 1 other site(s), so we broke the tie by mine status (past producers first), then USGS record quality, then name. USGS lists it as past producer for Silver, Iron, Copper. Minerals mentioned: Copper, Silver. Approx. location 36.942, -103.051. 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?

2
Producer

Was producing when the record was made.

2
Past Producer

Produced ore or material at some point in the past.

1
Occurrence

The mineral was noted here, without development.

Status terms come from USGS MRDS records.

Mineral cards

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

Minerals recorded here

Scoria 1

Commodities

Copper 3Silver 2Volcanic Materials 1Iron 1Gold 1

Sites

SiteCommodityMinerals recordedStatusApprox. location
Twin Mountain Rock QuarryVolcanic MaterialsScoriaProducer36.834, -103.882
Peacock Canyon ProspectsCopper—Past Producer36.911, -103.373
Black Mesa ProspectSilver, Iron, Copper—Past Producer36.942, -103.051
Folsom AreaGold—Occurrence36.923, -103.586
San Miguel MineCopper, Silver—Producer36.920, -103.981

Fossil collections

The Paleobiology Database lists 19 fossil collection records in Union County. These are research records, not public dig sites.

Nearby counties

Harding County · Colfax County · Taos County · Mora County · Quay County

New Mexico mineral guides

Back to all New Mexico counties.

Related articles

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