Black River Harbor: Rockhounding in Gogebic County, Michigan

Updated August 2026

Black River Harbor is a mapped rockhounding spot in Gogebic County, Michigan. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Check locally
County: Gogebic County
State: Michigan
Postcode: 49938
Coordinates: 46.66443, -90.04706

Geology at Black River Harbor

This spot sits on Keweenawan Supergroup: Copper Harbor Conglomerate, mapped as conglomerate that formed roughly 1600 to 1000 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: Keweenawan Supergroup: Copper Harbor Conglomerate
Age: 1600–1000 Ma (Mesoproterozoic)
Rock types: conglomerate
Elevation: 660 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 Black River Harbor

Best months: April to October. Typical highs run 80°F in midsummer and 23°F in midwinter, with winter lows near 5°F.

Climate normals: NOAA 1991-2020 monthlies, IRONWOOD #2 station (14 mi away), adjusted for elevation.

Land & collecting status

Confirm rules before collecting

Land status here is not confirmed. Verify with the managing agency before collecting — federal, state, and tribal rules differ.

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

Nearby rockhounding spots

Other rockhounding spots within driving distance of Black River Harbor.

Across the state line from Black River Harbor

Black River Harbor is close enough to the Michigan border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Black River Harbor FAQ

Where is Black River Harbor?+

Black River Harbor is in Gogebic County, Michigan, at 46.66443, -90.04706.

What rocks and minerals can you find at Black River Harbor?+

Black River Harbor is on the rockhounding map but no minerals are listed in our reference. Open RockHoundR to see what other rockhounds have logged.

Is collecting allowed at Black River Harbor?+

Confirm rules before collecting. Land status here is not confirmed. Verify with the managing agency before collecting — federal, state, and tribal rules differ. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Black River Harbor?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Black River Harbor?+

The most comfortable months at Black River Harbor are April to October.

How do I get to Black River Harbor?+

Open the directions link to navigate to 46.66443, -90.04706 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Michigan

See all 107 Michigan spots →

Open Black River Harbor on the map

Use the RockHoundR app for live land overlays, weather, geology, directions, and saved finds.