Formula: (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2.nH2O Monoclinic Description: Montmorillonite with pen for scale. From the mineral collection of Brigham Young University Department of Geology, Provo, Utah, Mineral Specimens 794. Courtesy of the U.S. Geological Survey Denver Library Photographic Collection. (Photo by …
Grant County
Pearls
Description: Pearls are hard nodular precipitates formed inside the shells of mollusks such as clams. They consist of layers of calcium carbonate, either in the form of calcite or aragonite held together by a horny …
Pyrite
Pyrite is the most common sulfide found in many environments. It is a common accessory mineral in igneous, sedimentary and metamorphic rocks. It also is abundant in most hydrothermal deposits. Only the most significant occurrences …
Quartz
Formula: SiO2 Hexagonal Description: Quartz is the most abundant mineral. It is an essential component of granitic igneous rocks, of sedimentary rocks such as sandstone and chert and of metamorphic rocks such as quartzites. It is a …
Smithsonite
Description: Massive to botryoidal smithsonite of a form originally called “dry bone ore” by miners. This was a major zinc ore in the mines of southwestern Wisconsin. From the Little Giant Mine, near Shullsburg, Lafayette …
Sphalerite
Formula: ZnS Isometric Description: Banded sphalerite, near Hazel Green in Lafayette County, Wisconsin. Sample is about 1 cm long. Sphalerite occurs in a wide range of hydrothermal environments. It is common with chalcopyrite in exhalative massive …
Depth to Bedrock in Grant County, Wisconsin
Depth-to-bedrock mapping of Grant County provides baseline information on unconsolidated surficial sediment thickness across the county. Bedrock aquifers in Grant County are susceptible to contamination from various land use activities, and depth to bedrock represents …
Take note: making observations in the field
Survey geologist Sarah Bremmer stands on the side of the road with a blaze-orange vest and a notebook. She is conducting fieldwork for a new geologic map and is in the process of thoroughly describing …
Geologic Map of the Fennimore and Mount Hope 7.5-Minute Quadrangles, Grant County, Wisconsin
The geologic map of the Fennimore and Mount Hope quadrangles includes 1:24,000-scale mapping of both surficial and bedrock geology. The mapping was initiated to support groundwater studies in the area. The map and accompanying report …
Geologic map of the Stitzer and western part of the Montfort 7.5-minute quadrangles, Grant County, Wisconsin
The geologic map of the Stitzer and western part of the Montfort quadrangles includes 1:24,000-scale mapping of both surficial and bedrock geology. This area occurs at the northern margin of the historic Upper Mississippi Valley …