Union County: Petrified Wood & Rose Agate Rockhounding in Union County, New Mexico

Updated July 2026

Union County is a mapped rockhounding spot in Union County, New Mexico. Reported finds include petrified wood, rose agate. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Union County
State: New Mexico
Coordinates: 36.99403, -103.00782

Geology at Union County

This spot sits on Entrada Sandstone, mapped as sandstone that formed roughly 175 to 160 million years ago. Sedimentary beds like these are the typical host for petrified and silicified wood, which weathers out as durable float on slopes and in washes.

Mapped unit: Entrada Sandstone
Age: 175–160 Ma (Middle Jurassic)
Rock types: sandstone
Elevation: 4,430 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 Union County

Best months: August to June. Typical highs run 93°F in midsummer and 51°F in midwinter, with winter lows near 19°F.

Climate normals: NOAA 1991-2020 monthlies, KENTON station (7 mi away).

Land & collecting status

Permission required before collecting

Requires landowner or agency permission before any collecting. Do not enter without explicit authorization.

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

Rockhound State Park — Collection rules
BLM New Mexico
New Mexico Bureau of Geology and Mineral Resources
Community submissions reviewed against published agency rules

Found at Union County

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 Union County.

Across the state line from Union County

Union County is close enough to the New Mexico border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Union County FAQ

Where is Union County?+

Union County is in Union County, New Mexico, at 36.99403, -103.00782.

What rocks and minerals can you find at Union County?+

Union County is reported to produce Petrified Wood, Rose Agate.

Is collecting allowed at Union County?+

Permission required before collecting. Requires landowner or agency permission before any collecting. Do not enter without explicit authorization. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Union County?+

A rock hammer, sturdy gloves, and a padded bag cover petrified wood hunting. Most pieces are surface float, so walking slopes and washes beats digging.

When is the best time to visit Union County?+

The most comfortable months at Union County are August to June.

How do I get to Union County?+

Open the directions link to navigate to 36.99403, -103.00782 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in New Mexico

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Open Union County on the map

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