Moselle Iron Mines: Amethyst & Arsenopyrite Rockhounding in Phelps County, Missouri

Quick details

Access

Public area

County

Phelps County

State

Missouri

Nearest road

County Road 7240

Postcode

65550

Coordinates

37.83458, -91.82879

Geology at Moselle Iron Mines

This spot sits on Roubidoux Formation, mapped as sandstone and chert that formed roughly 485 to 470 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

Roubidoux Formation

Age

485–470 Ma (Early Ordovician)

Rock types

sandstone and chert

Elevation

930 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.

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.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Moselle Iron Mines

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

• AmethystEncyclopedia →
• ArsenopyriteEncyclopedia →
• AzuriteEncyclopedia →
• ChalcopyriteEncyclopedia →
• HematiteEncyclopedia →
• MalachiteEncyclopedia →
• MarcasiteEncyclopedia →
• PyriteEncyclopedia →
• Smoky QuartzEncyclopedia →