Twin Peak: Andesine & Apatite Rockhounding in Millard County, Utah

Updated June 2026

Twin Peak is a mapped rockhounding spot in Millard County, Utah. Reported finds include andesine, apatite, augite, biotite, magnetite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Millard County
State: Utah
Coordinates: 38.78412, -112.73286

Geology at Twin Peak

This spot sits on Older alluvial-fan deposits, mapped as alluvium that formed within roughly the last 3 million years. Loose deposits like these are float-collecting ground: erosion keeps moving durable rocks and minerals into gravel bars, cutbanks, and washes.

Mapped unit: Older alluvial-fan deposits
Age: 3 Ma to present (Pleistocene)
Rock types: alluvium
Elevation: 5,300 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 Twin Peak

Best months: February to June. Typical highs run 93°F in midsummer and 41°F in midwinter, with winter lows near 15°F.

Climate normals: NOAA 1991-2020 monthlies, BLACK ROCK station (13 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

BLM Utah, Rockhounding overview
Utah Geological Survey, collecting guidelines
SITLA, surface use rules
Community submissions reviewed against published agency rules

Found at Twin Peak

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 Twin Peak.

Across the state line from Twin Peak

Twin Peak is close enough to the Utah border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Snake RangeWhite Pine County, Nevada · 78 mi awaySilver, Tungsten

Twin Peak FAQ

Where is Twin Peak?+

Twin Peak is in Millard County, Utah, at 38.78412, -112.73286.

What rocks and minerals can you find at Twin Peak?+

Twin Peak is reported to produce Andesine, Apatite, Augite, Biotite, Magnetite.

Is collecting allowed at Twin Peak?+

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 Twin Peak?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Twin Peak?+

The most comfortable months at Twin Peak are February to June.

How do I get to Twin Peak?+

Open the directions link to navigate to 38.78412, -112.73286 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Utah

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Open Twin Peak on the map

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