Searles Lake: Borax & Aphthitalite Rockhounding in San Bernardino County, California

Updated June 2026

Searles Lake is a mapped rockhounding spot in San Bernardino County, California. Reported finds include borax, aphthitalite, halite, hanksite. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: San Bernardino County
State: California
Coordinates: 35.73155, -117.32936

Geology at Searles Lake

This spot sits on alluvium and marine deposits, mapped as coarse alluvium that formed within roughly the last 5 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: alluvium and marine deposits
Age: 5 Ma to present (Pliocene to Holocene)
Rock types: coarse alluvium
Elevation: 1,620 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 Searles Lake

Best months: October to May. Typical highs run 108°F in midsummer and 60°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, TRONA station (4 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

BLM California — Recreational mineral collecting
California Geological Survey
CDFW — Suction Dredge Mining Permit Program
Community submissions reviewed against published agency rules

Found at Searles Lake

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 Searles Lake.

Searles Lake FAQ

Where is Searles Lake?+

Searles Lake is in San Bernardino County, California, at 35.73155, -117.32936.

What rocks and minerals can you find at Searles Lake?+

Searles Lake is reported to produce Borax, Aphthitalite, Halite, Hanksite.

Is collecting allowed at Searles Lake?+

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 Searles Lake?+

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 Searles Lake?+

The most comfortable months at Searles Lake are October 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 Searles Lake?+

Open the directions link to navigate to 35.73155, -117.32936 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in California

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Open Searles Lake on the map

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