- Platteville Limestone (MNopedia)
Platteville limestone is a distinctive building stone of southeastern Minnesota and southwestern Wisconsin characterized by its gray color, rough texture, and many fossils. It was heavily used in the early decades of the building of the Twin Cities and Faribault.
- Platteville Limestone (Wikipedia)
The Platteville Limestone is the Ordovician limestone formation in the sedimentary sequence characteristic of the upper Midwestern United States. It is characterized by its gray color, rough texture, and numerous fossils. Its type locality is Platteville, Wisconsin. It was heavily used in the early decades of the building of Minneapolis–Saint Paul and Faribault, Minnesota.