Sanilac County Lexington Park: Rockhounding in Sanilac County, Michigan

Quick details

Access

Public area

County

Sanilac County

State

Michigan

Postcode

48450

Coordinates

43.31555, -82.53406

Geology at Sanilac County Lexington Park

This spot sits on Berea Sandstone, mapped as sandstone that formed roughly 385 to 360 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

Berea Sandstone

Age

385–360 Ma (Late Devonian)

Rock types

sandstone

Elevation

640 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 Sanilac County Lexington Park

Best months: April to November. Typical highs run 78°F in midsummer and 30°F in midwinter, with winter lows near 16°F.

Climate normals: NOAA 1991-2020 monthlies, LEXINGTON WTP station (4 mi away).

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

• Michigan DNR — Rockhounding rules
• Michigan Geological Survey
• Isle Royale National Park — Rules
• Community submissions reviewed against published agency rules