Dumps near Esperanza Mine: Copper & Molybdenum Rockhounding in Pima County, Arizona

Quick details

Access

Public area

County

Pima County

State

Arizona

Nearest road

Elams Loop

Coordinates

31.86703, -111.12985

Geology at Dumps near Esperanza Mine

This spot sits on sedimentary and volcanic rocks, mapped as sandstone, siltstone, and conglomerate that formed roughly 170 to 145 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit

sedimentary and volcanic rocks

Age

170–145 Ma (Middle Jurassic to Late Jurassic)

Rock types

sandstone, siltstone, and conglomerate

Elevation

3,270 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 Dumps near Esperanza Mine

Best months: October to May. Typical highs run 98°F in midsummer and 66°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, GREEN VALLEY station (8 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 Arizona — Recreational Mineral Collecting
• Arizona Geological Survey
• Arizona State Land Department recreation permits
• Community submissions reviewed against published agency rules

Found at Dumps near Esperanza Mine

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

• CopperEncyclopedia →
• Molybdenum