Agua Fria Ranch: Agate & Agatized Wood Rockhounding in Brewster County, Texas

Updated June 2026

Agua Fria Ranch is a mapped rockhounding spot in Brewster County, Texas. Reported finds include agate, agatized wood. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Brewster County
State: Texas
Nearest road: Agua Fria Road
Coordinates: 29.52524, -103.67388

Geology at Agua Fria Ranch

This spot sits on Aguja Formation, mapped as clay that formed roughly 145 to 66 million years ago. Petrified wood typically travels as tough float, and worked gravels like these are exactly where weathered pieces tend to collect.

Mapped unit: Aguja Formation
Age: 145–66 Ma (Early Cretaceous to Late Cretaceous)
Rock types: clay
Elevation: 3,500 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 Agua Fria Ranch

Best months: September to April. Typical highs run 94°F in midsummer and 62°F in midwinter, with winter lows near 35°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, LAKE AMENT station (11 mi away).

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 Agua Fria Ranch

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 Agua Fria Ranch.

Agua Fria Ranch FAQ

Where is Agua Fria Ranch?+

Agua Fria Ranch is in Brewster County, Texas, at 29.52524, -103.67388. Nearest road: Agua Fria Road.

What rocks and minerals can you find at Agua Fria Ranch?+

Agua Fria Ranch is reported to produce Agate, Agatized Wood.

Is collecting allowed at Agua Fria Ranch?+

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 Agua Fria Ranch?+

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 Agua Fria Ranch?+

The most comfortable months at Agua Fria Ranch 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 Agua Fria Ranch?+

Open the directions link to navigate to 29.52524, -103.67388 in Google Maps. The nearest road is Agua Fria Road.

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