La Madera Mine: Mica Rockhounding in Rio Arriba County, New Mexico

Quick details

Access

Public area

County

Rio Arriba County

State

New Mexico

Nearest road

NM 519

Postcode

87539

Coordinates

36.39612, -106.02417

Geology at La Madera Mine

This spot sits on Los Pinos Formation of Lower Santa Fe Group, mapped as coarse alluvium and conglomerate that formed roughly 28 to 5 million years ago. Loose deposits like these are float-collecting ground: erosion keeps moving durable rocks and minerals into gravel bars, cutbanks, and washes.

Mapped unit

Los Pinos Formation of Lower Santa Fe Group

Age

28–5 Ma (Late Oligocene to Miocene)

Rock types

coarse alluvium and conglomerate

Elevation

6,610 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 La Madera Mine

Best months: February to November. Typical highs run 85°F in midsummer and 42°F in midwinter, with winter lows near 19°F.

Climate normals: NOAA 1991-2020 monthlies, EL RITO station (10 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

• Rockhound State Park — Collection rules
• BLM New Mexico
• New Mexico Bureau of Geology and Mineral Resources
• Community submissions reviewed against published agency rules

Found at La Madera Mine

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

• MicaEncyclopedia →