ROCKHOUND SCOUT
Launching soon

Find rockhounding hotspots along Texas highways

Rockhound Scout checks published geologic map data along state and U.S. highways, finds the stretches where one rock formation meets another, prioritizes drainage crossings, and writes you a field guide entry (Hotspot Card) for each one: where to look, what to watch for from the truck, and what you might find.

Simple Search Controls

The Rockhound Scout app home screen, showing region cards and the Find My Hotspots button.

Actual Sample Hotspot Card

A real Rockhound Scout hotspot card for the Baby Head Ridge Llanite Dike Roadcut, showing formation, directions, and what to look for.

The app itself: pick a region, tap Find My Hotspots, and get back a real hotspot card — this one for the Baby Head Ridge Llanite Dike Roadcut, one of the only sources of llanite on Earth.

How it works

  1. Pick a region or type your own Custom area. Choose a preset Texas region, or use Custom to type a town, area, or a plain sentence like “within 20 miles of my hotel at [address]” or “agatized petrified wood near Bryan, TX.”
  2. The app reads the maps. It finds nearby state and U.S. highways, samples the geologic map along each road, and prioritizes named drainages. Those contacts are where minerals, fossils, and petrified wood often concentrate.
  3. You get hotspot cards. Each card gives the formations on either side of the contact, named creeks nearby, driving directions from a nearby town, what to look for from the truck window, likely finds, and a Waze search term.

What’s in it

Preset regions

Llano Uplift, Three Rivers, Edwards Plateau, Big Bend, and the Cretaceous Shelf.

Custom search

Any spot in Texas. Type a town, address, or what gems/minerals you’re hunting. Included at no extra charge.

Map-based locations

Formation contacts come from searching published map and geologic data.

Informative & helpful write-ups

Top-shelf instructions, tips, and data for every hotspot — nothing generic or boilerplate.

Real finds

No stock photos here. These are the owner’s found treasures, pulled straight out of the ground by chasing similar Hotspot cards all over the great state of Texas.

Close-up of llanite showing salmon-pink and blue-grey quartz phenocrysts, with a quarter for scale.
Llanite, up closeSalmon-pink and storm-blue quartz phenocrysts locked in dark rock. This exact combination exists nowhere else on Earth.
The 300 lb llanite boulder from the Baby Head roadcut.
Llanite, the 300 lb boulderI am almost done polishing to expose a window into this beautiful stone.
A group of llanite pieces, both river-tumbled and jewelry-grade rough.
Llanite: river-tumbled and jewelry gradeThe rounded pieces are river-tumbled and weathered llanite. The sharper pieces, I call jewelry grade — a couple have been cut, revealing the hard, dark llanite underneath.
A Town Mountain Granite boulder showing swirled gneissic banding.
Town Mountain GraniteThose swirled bands are over a billion years of crushing pressure frozen in stone — the ancient basement the whole Llano Uplift sits on.
A granite boulder with a quarter for scale, next to pieces of vein quartz.
Granite & quartz specimensVein quartz stained rust-red by iron bleeding through old fractures. Found in dry creek beds on the Llano Uplift.
A mixed group of quartz and banded granite pieces.
A haul from the UpliftQuartz, banded granite, and iron-streaked float — a sample of how much variety turns up in a single afternoon out there.
A piece of petrified palm wood with a natural cavity, coin for scale.
Petrified palm wood — with opal insideThat dark cavity near the coin holds a genuine pocket of precious opal, confirmed under UV light. I suspect if cut, the center is full of opal.
A weathered face of petrified wood showing growth-ring banding.
Petrified palm wood, frozen mid-decay — 2nd sidePalm isn’t a tree, so it never grew rings. It’s built from vascular bundles instead, with the softer tissue between them decaying first — then every bit of it, fast-decaying and slow alike, replaced by silica cell by cell.
A group of assorted petrified wood pieces found at different locations.
Petrified wood, LaGrange & Three RiversDriftwood-pale to deep amber — none of these came from the same spot. Using the app to find the next hotspot and treasured specimen is incredibly fun.
Vuggy limestone from the Glen Rose Formation with a small ring-shaped piece in front.
Limestone, honeycombed by timeEvery hole here is where a softer streak of Glen Rose limestone simply dissolved away. The little ring in front formed the same way — a natural stone donut.
Chert nodules and a fossilized rudist clam shell.
Chert & a 100-million-year-old clam clusterThe large ribbed fossil is a cluster of rudists — extinct reef-building bi-valves from the sea that once covered Texas. Far left: a river-tumbled rudist fossil. Chert fossils (bottom stones) in a variety of Hill Country specimen colors.

Tap any photo to see it full size.

Scans can take a minute to run — be patient.

Rockhound Scout doesn’t pull from some pre-made list. Each time you press the button “Find My Hotspots,” the app is out there live: pulling real highway data, sampling the geologic map mile by mile along every road in your target area, and cross-referencing rock formations in real time. Scans can take a minute or so to run — be patient. There is a tremendous amount of data to query. If you’re the type who finds that kind of thing impressive rather than annoying — welcome, you’re among friends.

Pricing

ONE-TIME PURCHASE
$25
200 SCANS
  • 200 scans, preset regions or Custom
  • Custom area search included
  • Scans never expire
  • No subscription and no recurring charges
CHECKOUT OPENS SOON

One “scan” is one tap of Find My Hotspots. A scan that ends in an error, or that finds no hotspots, isn’t deducted. See the Refund & Dispute Policy.

Straight talk about what this is

This is a research tool, not a guarantee. Geologic maps can’t show every small vein or outcrop, so a marked stretch is a starting point: check both sides of the road nearby. Most Texas land is privately owned, so always get the landowner’s permission before collecting, park off the highway shoulder, and follow all traffic and land-use laws. Please read the Terms of Service.

Questions

Is this a subscription?

No. It’s a one-time $25 purchase for 200 scans. Nothing renews and there’s nothing to cancel.

Do scans expire?

No. Use them whenever you like.

What counts as a scan?

One tap of Find My Hotspots, for a preset region or a Custom search. If the scan ends in an error or returns no hotspots, it isn’t deducted.

Can I get a refund?

We don’t refund unused scans or change-of-mind purchases. If we charge you by mistake, a scan is wrongly deducted, or the app is broken for an extended period, we’ll make it right. Details are in the Refund & Dispute Policy.

Does it cover places outside Texas?

Not yet. Rockhound Scout currently works only for Texas.

Where does the data come from?

Rock formation data comes from Macrostrat, a public database that compiles published geologic maps from sources including the U.S. Geological Survey and the Texas Bureau of Economic Geology. Roads and creek names come from OpenStreetMap. AI is used only to write the descriptions.

How do I contact you?

Email RockhoundScoutApp@gmail.com.

“I built this app to work the way I already hunt: pull up the geologic map for my target area, then picture it laid over satellite imagery, watching for the drainages that cut under public highways. I figured that process would make a good app. It turned out far better than I expected — I hope you enjoy using it as much as I’ve enjoyed building it.” — John Thompson, founder, Rockhound Scout