Best spot

Llanite Roadcut on Highway 16: Llanite & Blue Quartz Rockhounding in Llano County, Texas

Updated August 2026

The roadcut on Texas Highway 16 about nine miles north of Llano slices through the only known outcrop of llanite, a 1.1-billion-year-old rhyolite porphyry flecked with blue quartz crystals found essentially nowhere else on Earth. The blue color comes from microscopic ilmenite inclusions in the quartz, set in a matrix studded with reddish microcline feldspar. It is the single publicly reachable exposure of the rock. Reported finds include llanite, blue quartz. Below: coordinates, access notes, nearby spots, and trip-planning links.

Llanite Roadcut on Highway 16 photos

Public image records connected to this spot or its reported material.

1 photo

Llanite from the Highway 16 roadcut north of Llano, showing blue quartz crystals in pink feldspar

Quick details

Access: Public area
County: Llano County
State: Texas
Coordinates: 30.87937, -98.65394

Geology at Llanite Roadcut on Highway 16

This spot sits on Valley Spring Gneiss, mapped as paragneiss that formed roughly 2500 to 540 million years ago. Metamorphic terrain like this typically carries quartz veins and sweats, and weathered crystals tend to end up in the soils and streams below.

Mapped unit: Valley Spring Gneiss
Age: 2500–540 Ma (Proterozoic)
Rock types: paragneiss
Elevation: 1,350 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 Llanite Roadcut on Highway 16

Best months: September to May. Typical highs run 95°F in midsummer and 61°F in midwinter, with winter lows near 32°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, LLANO station (9 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 Llanite Roadcut on Highway 16

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 Llanite Roadcut on Highway 16.

Llanite Roadcut on Highway 16 FAQ

Where is Llanite Roadcut on Highway 16?+

Llanite Roadcut on Highway 16 is in Llano County, Texas, at 30.87937, -98.65394.

What rocks and minerals can you find at Llanite Roadcut on Highway 16?+

Llanite Roadcut on Highway 16 is reported to produce Llanite, Blue Quartz.

Is collecting allowed at Llanite Roadcut on Highway 16?+

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 Llanite Roadcut on Highway 16?+

A rock hammer, a small pry bar, gloves, and safety glasses cover most crystal ground. A screen helps in loose pocket soil, and newspaper protects points on the way out.

When is the best time to visit Llanite Roadcut on Highway 16?+

The most comfortable months at Llanite Roadcut on Highway 16 are September to May. Summer heat here is intense, so carry more water than you think you need and work the early morning.

How do I get to Llanite Roadcut on Highway 16?+

Open the directions link to navigate to 30.87937, -98.65394 in Google Maps. Some spots are remote, so check road conditions before driving out.

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