Poplar Beach: Agate Rockhounding in San Mateo County, California

Updated August 2026

Poplar Beach is a mapped rockhounding spot in San Mateo County, California. Reported finds include agate. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: San Mateo County
State: California
Nearest road: Coastal Trail
Postcode: 94019
Coordinates: 37.45522, -122.44480

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 Poplar Beach

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

Agate Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Poplar Beach.

Poplar Beach FAQ

Where is Poplar Beach?+

Poplar Beach is in San Mateo County, California, at 37.45522, -122.44480. Nearest road: Coastal Trail.

What rocks and minerals can you find at Poplar Beach?+

Poplar Beach is reported to produce Agate.

Is collecting allowed at Poplar Beach?+

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 Poplar Beach?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

How do I get to Poplar Beach?+

Open the directions link to navigate to 37.45522, -122.44480 in Google Maps. The nearest road is Coastal Trail.

More rockhounding in California

See all 104 California spots →

Open Poplar Beach on the map

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