New River Area Streams: Agate & Chalcedony Rockhounding in Maricopa County, Arizona

Plan your visit

Generally open to casual rockhounding

County

Maricopa County

State

Arizona

Nearest road

West New River Road

Postcode

85087

Coordinates

33.91942, -112.10474

Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.

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.

Best time to visit New River Area Streams

Comfortable months (45 to 90°F highs)

Best months: October to April. Typical highs run 105°F in midsummer and 66°F in midwinter, with winter lows near 43°F. Monsoon storms peak in July and August and can flood washes fast.

Climate normals: NOAA 1991-2020 monthlies, CAREFREE station (14 mi away), adjusted for elevation.

Geology at New River Area Streams

This spot sits on volcanic rocks, mapped as basalt, andesite, and dacite that formed roughly 41 to 7 million years ago. Volcanic ground like this is where agate, jasper, and other chalcedony typically form, filling old gas pockets and fracture seams in the flow rock.

Mapped unit

volcanic rocks

Age

41–7 Ma (Late Eocene to Late Miocene)

Rock types

basalt, andesite, and dacite

Elevation

2,100 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.

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 Arizona, Recreational Mineral Collecting
• Arizona Geological Survey
• Arizona State Land Department recreation permits
• Community submissions reviewed against published agency rules