Bonanza Flat: Grossularite Garnet Rockhounding in Wasatch County, Utah

Updated June 2026

Bonanza Flat is a mapped rockhounding spot in Wasatch County, Utah. Reported finds include grossularite garnet. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Permission required
County: Wasatch County
State: Utah
Nearest road: Fireweed Way
Postcode: 84055
Coordinates: 40.59472, -111.51627

Geology at Bonanza Flat

This spot sits on ground mapped as Till of Pinedale age 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: Till of Pinedale age
Age: 3 Ma to present (Pleistocene)
Elevation: 8,490 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 Bonanza Flat

Best months: April to October. Typical highs run 79°F in midsummer and 27°F in midwinter, with winter lows near 5°F. At about 8,490 ft, snow can block access from late fall well into spring, so check conditions outside of summer.

Climate normals: NOAA 1991-2020 monthlies, SNAKE CREEK POWERHOUSE station (3 mi away), adjusted for elevation.

Land & collecting status

Permission required before collecting

Requires landowner or agency permission before any collecting. Do not enter without explicit authorization.

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 Bonanza Flat

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Grossularite Garnet Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Bonanza Flat.

Across the state line from Bonanza Flat

Bonanza Flat 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.

Fort BridgerUinta County, Wyoming · 79 mi awayAgate, Jasper, Silicified Agate

Bonanza Flat FAQ

Where is Bonanza Flat?+

Bonanza Flat is in Wasatch County, Utah, at 40.59472, -111.51627. Nearest road: Fireweed Way.

What rocks and minerals can you find at Bonanza Flat?+

Bonanza Flat is reported to produce Grossularite Garnet.

Is collecting allowed at Bonanza Flat?+

Permission required before collecting. Requires landowner or agency permission before any collecting. Do not enter without explicit authorization. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Bonanza Flat?+

A rock hammer, a sieve, and a small shovel work well for garnet-type minerals, which concentrate as resistant grains in soils and creek gravels.

When is the best time to visit Bonanza Flat?+

The most comfortable months at Bonanza Flat are April to October. At about 8,490 ft, snow can block access from late fall well into spring, so check conditions outside of summer.

How do I get to Bonanza Flat?+

Open the directions link to navigate to 40.59472, -111.51627 in Google Maps. The nearest road is Fireweed Way.

More rockhounding in Utah

See all 246 Utah spots →

Open Bonanza Flat on the map

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