Plum Creek

Plum Creek, near Rock Elm in Pierce County, Wisconsin, is one of the odder rockhounding footnotes in the Midwest: it's a confirmed diamond locality. Between 1887 and 1890, flour gold was worked by panning and sluicing along Plum Creek, Rock Elm Creek, and their tributaries — and at least 10 small yellowish diamonds turned up during that placer gold operation between 1890 and 1892 [1]. It wasn't a fluke: in 1985, Superior Oil Company's minerals division confirmed significant placer gold still present in the area, though nobody has ever located the actual bedrock source of either the gold or the diamonds [1]. The historic placer ground is now inside Nugget Lake County Park [1] — a real, public, and unusually well-documented site for a state not known for either gold or diamonds.

Nugget Lake County Park, near Rock Elm, Pierce County, Wisconsin [1][2]. This is a maintained Pierce County park with public access.

Panning and sluicing is the historically documented method — this is placer material in creek gravel, not hard-rock digging. No bedrock source for the gold or diamonds has ever been located, so don't expect a "mother lode" — this is fine-material panning, patience required.

Plum Creek's historic placer ground sits inside Nugget Lake County Park, Pierce County [1] — confirm current park rules on panning/collecting with Pierce County Parks directly, since county park policies on removing material can vary and weren't independently confirmed for this specific park in the sources found.