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Black Hawk County — Rockhounding in Black Hawk County, Iowa

Updated July 2026

The Cedar River valley through Black Hawk County is the home ground of the Iowa coldwater agate, a pale blue-gray to cream banded agate weathered from Devonian limestone and reworked into the river gravels. It occurs alongside true Lake Superior agates carried in by glaciers, giving the local bars two distinct agate types. The Cedar River constantly refreshes its gravel, so productive ground shifts with each season. Reported finds include coldwater agate. Below: coordinates, access notes, nearby spots, and trip-planning links.

Black Hawk County photos

Public image records connected to this spot or its reported material.

1 photo

Map showing Black Hawk County in Black Hawk County, Iowa

Quick details

Access
Public area
State
Iowa
Nearest road
North Elk Run Road
Postcode
50703

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 Black Hawk County

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 Black Hawk County.

Across the state line from Black Hawk County

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

Black Hawk County FAQ

Why is Black Hawk County one of the best rockhounding spots in Iowa?+
The Cedar River valley through Black Hawk County is the home ground of the Iowa coldwater agate, a pale blue-gray to cream banded agate weathered from Devonian limestone and reworked into the river gravels. It occurs alongside true Lake Superior agates carried in by glaciers, giving the local bars two distinct agate types. The Cedar River constantly refreshes its gravel, so productive ground shifts with each season.
Where is Black Hawk County?+
Black Hawk County is in Black Hawk County, Iowa, at 42.52178, -92.25494. Nearest road: North Elk Run Road.
What rocks and minerals can you find at Black Hawk County?+
Black Hawk County is reported to produce Coldwater Agate.
Is collecting allowed at Black Hawk County?+
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. Always confirm current rules with the managing agency before a trip.
How do I get to Black Hawk County?+
Open the directions link to navigate to 42.52178, -92.25494 in Google Maps. The nearest road is North Elk Run Road.

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