Negwegon State Park: Puddingstone & Petoskey Stone Rockhounding in Alcona County, Michigan

Updated August 2026

Negwegon State Park is a mapped rockhounding spot in Alcona County, Michigan. Reported finds include puddingstone, petoskey stone, granite, gneiss, quartz, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Paid / fee dig
County: Alcona County
State: Michigan
Coordinates: 44.85515, -83.32462

Geology at Negwegon State Park

This spot sits on Antrim Shale, mapped as black shale 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: Antrim Shale
Age: 385–360 Ma (Late Devonian)
Rock types: black shale
Elevation: 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 Negwegon State Park

Best months: April to October. Typical highs run 74°F in midsummer and 26°F in midwinter, with winter lows near 14°F.

Climate normals: NOAA 1991-2020 monthlies, HARRISVILLE SP station (14 mi away).

Land & collecting status

Pay-to-dig site

This is a fee-dig location. Hours, prices, and what you can keep vary by operator. Call ahead before driving out.

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

Found at Negwegon State Park

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

Nearby rockhounding spots

Other rockhounding spots within driving distance of Negwegon State Park.

Negwegon State Park FAQ

Where is Negwegon State Park?+

Negwegon State Park is in Alcona County, Michigan, at 44.85515, -83.32462.

What rocks and minerals can you find at Negwegon State Park?+

Negwegon State Park is reported to produce Puddingstone, Petoskey Stone, Granite, Gneiss, Quartz, Gowganda Tillite, Charlevoix Stone.

Is collecting allowed at Negwegon State Park?+

Pay-to-dig site. This is a fee-dig location. Hours, prices, and what you can keep vary by operator. Call ahead before driving out. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Negwegon State Park?+

A rock hammer, a small pry bar, gloves, and safety glasses cover most crystal ground. A screen helps in loose pocket soil, and newspaper protects points on the way out.

When is the best time to visit Negwegon State Park?+

The most comfortable months at Negwegon State Park are April to October.

How do I get to Negwegon State Park?+

Open the directions link to navigate to 44.85515, -83.32462 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Michigan

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Open Negwegon State Park on the map

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