Area Near Jenson Quarry: Hornblende Rockhounding in Riverside County, California

Updated June 2026

Area Near Jenson Quarry is a mapped rockhounding spot in Riverside County, California. Reported finds include hornblende. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Public area
County: Riverside County
State: California
Nearest road: Sierra Avenue
Postcode: 92509
Coordinates: 34.02568, -117.43323

Geology at Area Near Jenson Quarry

This spot sits on ground mapped as Marble, Peninsular Ranges that formed roughly 540 to 250 million years ago. Metamorphic rock like this weathers into resistant float, and minerals that survive transport typically concentrate in nearby drainages.

Mapped unit: Marble, Peninsular Ranges
Age: 540–250 Ma (Paleozoic)
Elevation: 1,130 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 Area Near Jenson Quarry

Best months: September to June. Typical highs run 92°F in midsummer and 67°F in midwinter, with winter lows near 43°F.

Climate normals: NOAA 1991-2020 monthlies, RIVERSIDE MUNI AP station (5 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 California, Recreational mineral collecting
California Geological Survey
CDFW, Suction Dredge Mining Permit Program
Community submissions reviewed against published agency rules

Found at Area Near Jenson Quarry

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

Hornblende Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Area Near Jenson Quarry.

Area Near Jenson Quarry FAQ

Where is Area Near Jenson Quarry?+

Area Near Jenson Quarry is in Riverside County, California, at 34.02568, -117.43323. Nearest road: Sierra Avenue.

What rocks and minerals can you find at Area Near Jenson Quarry?+

Area Near Jenson Quarry is reported to produce Hornblende.

Is collecting allowed at Area Near Jenson Quarry?+

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 Area Near Jenson Quarry?+

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 Area Near Jenson Quarry?+

The most comfortable months at Area Near Jenson Quarry are September to June.

How do I get to Area Near Jenson Quarry?+

Open the directions link to navigate to 34.02568, -117.43323 in Google Maps. The nearest road is Sierra Avenue.

More rockhounding in California

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Open Area Near Jenson Quarry on the map

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