Chinati Mts: Agate & Chalcedony Rockhounding in Presidio County, Texas

Updated June 2026

Chinati Mts is a mapped rockhounding spot in Presidio County, Texas. Reported finds include agate, chalcedony, jasper. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Presidio County
State: Texas
Coordinates: 30.00039, -104.35293

Geology at Chinati Mts

This spot sits on Bluff Mesa Formation, mapped as limestone that formed roughly 145 to 100 million years ago. Chert and agate nodules typically form inside carbonate rock like this and weather out as tough, waxy lumps in soils and creek beds.

Mapped unit: Bluff Mesa Formation
Age: 145–100 Ma (Early Cretaceous)
Rock types: limestone
Elevation: 4,690 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 Chinati Mts

Best months: September to April. Typical highs run 94°F in midsummer and 61°F in midwinter, with winter lows near 27°F. Summer heat here is intense, so carry more water than you think you need and work the early morning.

Climate normals: NOAA 1991-2020 monthlies, CANDELARIA station (22 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

Texas Parks and Wildlife Department
Bureau of Economic Geology, Texas geology
Big Bend National Park, Rules
Community submissions reviewed against published agency rules

Found at Chinati Mts

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 Chinati Mts.

Chinati Mts FAQ

Where is Chinati Mts?+

Chinati Mts is in Presidio County, Texas, at 30.00039, -104.35293.

What rocks and minerals can you find at Chinati Mts?+

Chinati Mts is reported to produce Agate, Chalcedony, Jasper.

Is collecting allowed at Chinati Mts?+

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 Chinati Mts?+

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 Chinati Mts?+

The most comfortable months at Chinati Mts are September to April. Summer heat here is intense, so carry more water than you think you need and work the early morning.

How do I get to Chinati Mts?+

Open the directions link to navigate to 30.00039, -104.35293 in Google Maps. Some spots are remote, so check road conditions before driving out.

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Open Chinati Mts on the map

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