Formula: Au Isometric
Description: Gold is usually found in hydrothermal deposits where it forms at a wide range of temperatures and geological settings. Gold may form in exhalative deposits formed on the sea floor associated with Archean basaltic sequences known as greenstone belts. It may form in veins associated with large granite intrusions associated with mountain building. It may also form in veins formed along major fault zones. Gold in veins is associated with sulfides, quartz, and calcite.
Gold is resistant to weathering, hence is often freed from the surrounding rock and redeposited as sediment. Because gold has a high density, it tends to settle out readily and be trapped with coarser sediments. Where current action is strong, lighter materials are preferentially washed away, concentrating the gold in placer deposits. In submerged gold-bearing sediments, slight shaking of the sedimentary column will cause the gold to sift down toward the bottom of the deposit. These tendencies result in the gold accumulating along the contacts between sediment and underlying bedrock. Cracks and crevices in bedrock over which a river rushes or has rushed are good places to prospect. In placers, gold is associated with other dense or “heavy” minerals such as garnet, magnetite, ilmenite, and even diamonds. Gold is also found in conglomerates that are lithified placer deposits.
Gold has been reported from a number of places in Wisconsin, but the known deposits are all small and not economically viable. In researching gold reports, be aware that salting and fraudulent reports do occur and misidentification of materials such as pyrite and even bronzy-colored biotite for gold is common. The locations of suspected gold mines might also be vaguely located or deliberately mislocated in the literature.
Gold in small amounts can probably be found in placers in any county. Wisconsin glacial sediments contain small amounts of gold, and most Wisconsin streams are reworking some glacial sediment. Weekend panning can be a fun recreational activity, as long as one’s expectations for valuable finds are not too high. Wisconsin drift gold is generally in very small particles, constituting what is termed “flour gold,” with true nuggets being exceedingly rare. As such, skill and practice are necessary in being an effective “panner.” The associated sand-sized “heavy minerals” such as red garnet and black magnetite sand are interesting in their own right. Rarely, diamonds may also turn up during gold placer mining, as was the case along Plum Creek in Pierce County.
Check with the Wisconsin DNR and property owners before doing any panning in Wisconsin.
ASHLAND COUNTY: Old newspaper articles report a significant show of gold values at the Northern Belle Mine, W 1/2 SW Sec. 22 T.45N R.4W west of Penokee Gap. Cox (2002) compiled additional references indicating silver was also found. Exploration for gold has also occurred in sections 15, 22, 23 and 34 in T.45N R.4W (U.S.G.S., 1976). Cox (2002) describes attempts to placer mine in Brunschweiler Creek in sec. 22. during the 1880s. Gold, copper, and silver were worked briefly in an operation called the Chicago Mine between 1879 and 1881 in the north 1/2 of sec. 22 (Cox, 2002). Other operations of this same era and extent were in NE sec. 16, T44N R3W; NW sec. 6 T44N R5W, SE sec. 12 T45N R3W (Cox, 2002).
BAYFIELD COUNTY: Exploration for gold was carried out in the SW Sec. 2 and the NW Sec. 11 (Davis Hill) in T.44N R.6W north of Namekagon Lake (USGS, 1976). At Davis Hill, the gold was found in a conglomerate that also showed some silver and copper values (WGNHS files).
CLARK COUNTY: A trace of gold was detected by assay of a quartz vein cutting a talc and chlorite bearing schist “from Clark County.” Associated minerals were pyrite, magnetite, and arsenopyrite (Irving, 1874b).
DANE COUNTY: Placer gold can reportedly be panned along Black Earth Creek near Cross Plains (Maslowski, 1985).
DOUGLAS COUNTY: Flakes of native gold were reported in fine-grained diabase found on the “Federal Copper Mining Property” in the south-west corner of Douglas County. The rock supposedly assayed at $9.00 per ton in 1902 (Thomas, 1902).
— Placer gold can reportedly be panned along the Poplar and Middle Rivers (Maslowski, 1985).
DUNN COUNTY: A shaft, possibly for the exploitation of alluvial gold, is found near Knapp in Sec. 16 T.28N R.14W (Olcott, 1970).
EAU CLAIRE COUNTY: Recovery of gold from sediment collecting in crevices in bedrock at Big Falls (SW Sec. 13 T.27N R.8W) was rumored in the 1930′s (WGNHS files, 1985).
FOREST COUNTY: Gold is a minor component of the Crandon massive sulfide deposit in sec. 25 T.35N R.12E. It is here associated with sphalerite, chalcopyrite, and galena (WGNHS files, 1985).
IRON COUNTY: Exploration for gold took place at a few sites in the county in the 1800s, with little or no production. Sites mentioned are the Eagle prospect in T45N R.2E and the Maxim prospect in sec. 10 T.45N R.1W. (Cox, 2002).
LAFAYETTE COUNTY: A single grain of native gold was found in drill core taken from the “Nigger Jim” mine, south of Rewey at the NE SW Sec. 32 T.4N R.1E. The gold was associated with galena, barite, and pyrite (Heyl et. al., 1959; Taylor, 1964).
MARATHON COUNTY: Gold was found as tiny grains 0.5 mm in maximum diameter in a pocket in a pegmatite dike along the east edge of the Wausau pluton. The gold apparently formed by the alteration of the gold telluride, calaverite (Falster, 1987).
— Gold is reported as occurring at several localities around Mosinee and Wausau in Sec. 8 T.26N R.7E, Sec. 32 T.27N R.7E, Sec. 13 T.27N R.8E and Sec. 24 T.28N R.7E (Dutton and Bradley, 1970).
— Gold in quartz veins occurs at the Reef property prospected by Niranda about 12 miles E. of Wausau. The explored reserves were estimated at between 120,000â€“140,000 ounces. Some of the gold is visible as flakes and small crystals (Anonymous, 1991).
— Gold associated with pyrite, chalcopyrite, sphalerite and malachite is found in chlorite schist near Eason just southwest of the center of Sec. 26 T.29N R.9E. A 200-foot deep shaft was sunk at this locality, but production, if any, was minor (LaBerge and Myers, 1983).
MARINETTE COUNTY: An exploration shaft was sunk in the NE SW Sec. 16 T.36N R.21E, finding gold running 0.01 oz/ton with silver values in a “porphyroblastic argillite” east of Beecher. This deposit, which is apparently small and has never been mined, is referred to both as the “Micauno exploration shaft” and the “old Victor Smeister prospect” (WGNHS file, 1985).
— At the “Archie gold prospect,” west of Beecher, minor gold values were found in 1937 in east-west trending quartz veins cutting greenstone, gabbro, and quartz diorite. The location of the prospect is given as SW SW Sec. 8 and NE Sec. 17 T.36N R.20E (WGNHS files, 1985).
ONEIDA COUNTY: Gold is a minor component of the Pelican River massive sulfide body in Sec. 29 T.36N R.10E south of Rhinelander. Gold with silver and electrum occurs in the Lynn massive sulfide deposit (Kennedy et. al., 1991).
PIERCE COUNTY: Flour gold was worked in 1887â€“1890 by panning and sluicing placer deposits along Rock Elm Creek, Plum Creek and their tributaries south of the town of Rock Elm (T.26N R.15W). Over a dozen tiny diamonds were also recovered during the operations (Cannon and Mudrey, 1981). More recently, in 1985 exploration by the minerals division of the Superior Oil Company confirmed the existence of significant placer gold in the area but was unable to locate the bedrock source (W.S. Cordua field notes).
POLK COUNTY: Placer gold as small flakes was reported from a glacial drift deposit resting unconformably on Cambrian shales along the St. Croix Valley north of St. Croix Falls in the West 1/2 of sections 18, 19, and 30 T.34N R.18W (Thomas, 1902). Thomas also reported the finding of flakes and nuggets in sediment in crevices and joints in the basalt bedrock in the St. Croix Dalles in SW Sec. 30 T.34N R.18W. Residents would flock onto the outcrop in search of gold whenever the river level was low because of the closing of a logging dam upstream.
RUSK COUNTY: Gold occurs as flakes and masses in the massive sulfide ore body of the Flambeau deposit south of Ladysmith. It is found in the gossan as well as in quartz-rich pods and veins in the supergene zone where it is associated with sphalerite, chalcopyrite, and galena (LaBerge, 1995, Rosemeyer, 1997).
TAYLOR COUNTY: Tiny gold xls occur in quartz-rich gossan in the Bend deposit, NW sec. 2 T.32N. R.2W., northeast of Gilman (DeMatties and Rowell, 1991).