From what I have read is that the gold in WI will be found in the morraine ares which are visible in Kettle Morraine State Park . Look for any streams that cut through the morraines and do some testing from there and down stream if the park service will let you .

As far as the hardrock mining in Wi I don't think there was any major deposits in the State but gold has been found with some other minerals that are being mined there .

Born and raised in WI.

Good Luck to you !

Mike (AZ)