Calumet Waterworks Park: Lake Superior Agate & Prehnite Rockhounding in Houghton County, Michigan

Updated August 2026

Calumet Waterworks Park is a mapped rockhounding spot in Houghton County, Michigan. Reported finds include lake superior agate, prehnite, natrolite, mesolite, yooperlite, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Check locally
County: Houghton County
State: Michigan
Coordinates: 47.27413, -88.52982

Best time to visit Calumet Waterworks Park

Best months: April to October. Typical highs run 77°F in midsummer and 24°F in midwinter, with winter lows near 12°F.

Climate normals: NOAA 1991-2020 monthlies, HANCOCK HOUGHTON CO AP station (8 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

Found at Calumet Waterworks 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 Calumet Waterworks Park.

Across the state line from Calumet Waterworks Park

Calumet Waterworks Park 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.

Pigeon PointCook County, Minnesota · 68 mi awayChalcocite, Chalcopyrite, Pyrite

Calumet Waterworks Park FAQ

Where is Calumet Waterworks Park?+

Calumet Waterworks Park is in Houghton County, Michigan, at 47.27413, -88.52982.

What rocks and minerals can you find at Calumet Waterworks Park?+

Calumet Waterworks Park is reported to produce Lake Superior Agate, Prehnite, Natrolite, Mesolite, Yooperlite, Patricianite, Chlorastrolite, Copper.

Is collecting allowed at Calumet Waterworks Park?+

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 Calumet Waterworks Park?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Calumet Waterworks Park?+

The most comfortable months at Calumet Waterworks Park are April to October.

How do I get to Calumet Waterworks Park?+

Open the directions link to navigate to 47.27413, -88.52982 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Michigan

See all 107 Michigan spots →

Open Calumet Waterworks Park on the map

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