his is Wisconsin's sesquicentennial year. In addition to dairy farms, breweries, bratwurst, and Packers football, Wisconsin G T also has a diverse geology and a history rich in mineral production. This compilation of the state's mineral localities is part of its sesquicentennial celebration.Much of Wisconsin's settlement was initially spurred by the lead-zinc mining in its southwest comer, a heritage preserved by the figure of a miner on its state seal. Its mineral localities, however, are not well known beyond its borders. Many of them are now nearly forgotten, abandoned, and overgrown. In this respect, Wisconsin represents a frontier state for the mineral collector. A renaissance in the study of the state's minerals is now underway with the discovery of high-quality minerals from several new localities, including the Flambeau copper mine near Ladysmith (Rosemeyer 1999, the Vulcan Materials quarry in Racine (Scovil 1994), the pegmatites of Florence County (Koehier 1989) and the Wausau area (Falster 1987), and the metavolcanic rocks near Stevens Point (Buchholz 1996).This index summarizes and highlights what has been found in Wisconsin in the past 150 years and points the way to new Dr William S. Cordua is a professor of geology at the University of Wisconsin-River Falls where he teaches mineralogy and petrology among other courses.