Where to Find Chalcedony in Michigan
Michigan has 5 mapped collecting spots that report chalcedony, spread across 5 counties. 3 of the spots are on land mapped as publicly accessible, and 1 is a fee-dig site.
Spot list checked against source data on April 1, 2026.
Every chalcedony spot we track in Michigan
Best spotKeweenaw PointKeweenaw County, MichiganPublic access · Keweenaw Agate, Thomsonite, Datolite +2
Best spotLake Superior Beach (Ontonagon)Ontonagon County, MichiganPublic access · Keweenaw Agate, Thomsonite, Chalcedony +1
Two Hearted River State Forest CampgroundLuce County, MichiganFee dig · Unakite, Epidote, Chert +16
McClain State ParkHoughton County, MichiganPermission required · Adularia, Chalcedony, Chert +8
Michigamme MineMarquette County, MichiganPublic access · Chalcedony, Hematite, Jaspilite
Standout chalcedony spots in Michigan
Hand-picked from the full list above, with the reason each one earns a trip.
Keweenaw Point
Keweenaw County
The exposed Lake Shore Traps along the wave-washed tip of the Keweenaw Peninsula carry agate-filled amygdules and datolite, with larger Keweenaw agates working loose from a narrow gravel band at the waterline.
Lake Superior Beach (Ontonagon)
Ontonagon County
The Lake Superior shoreline around Ontonagon is among the most agate-rich in Michigan, with the stretch toward Copper Harbor noted for unusually heavy agate cover along with quartz, jasper, and occasional copper.
Best counties for chalcedony in Michigan
Ranked by the number of mapped chalcedony spots. County links open the full rockhounding page for that county.
Before you go
Read the chalcedony identification guide so you know what a keeper looks like in the field: Chalcedony in the encyclopedia.
