Formula: BaSO4 Orthorhombic
Description: Baryte is found general in low temperature hydrothermal deposits. It is most common in Wisconsin in the Upper Mississippi Valley zinc-lead district in Grant, Iowa, and Lafayette Counties where it is associated with galena, sphalerite, marcasite, pyrite, smithsonite, calcite, and dolomite. (Heyl et al., 1959). Its habit in the district was a white, gray, or brownish coarse cleavable masses, platy to bladed crystals, fibrous veins, or fine-grained banded nodular to colloform masses. In the shaley rocks associated with the ore bodies, baryte may occur as “irregular 2 to 6 inch spherical masses made up of lath-shaped to acicular crystals” with cores of galena or sphalerite (Mullens, 1964). Heyl et al. (1959) describe the coarse barite as generally representing an earlier generation that was then locally etched and dissolved with the finer grained barite precipitating later. At a few localities in this district it was sufficiently abundant to serve as an ore of barium. Baryte also notably occurs in the pegmatites near Wausau, Marathon County, and as crystals in veins in the iron formation in Iron County, most notably the Montreal Mine.
DOUGLAS COUNTY: A vein bearing baryte, with siderite and bornite, was found at the Mabel Nelson quarry, south of South Range.
GRANT COUNTY: Fairly widespread component of the zinc-lead ores of the Upper Mississippi Valley zinc-lead district. Many of the mines listed under galena and sphalerite in this county are also baryte localities. Some of the more important occurrences in the county are listed below.
— Massive baryte is found in the Platteville subdistrict, most notably at the Trego Mine in sec. 21 T.2N. R.1E. (Agnew, 1963).
— White platy crystals occur with pale yellow sphalerite, pyrite and marcasite at the Beetown Mine, E. quarter corner of sec. 29 T.4N. R.4W. (Heyl et al., 1959).
— Found at the Lafollette Miner near Cokerville in the NW NE Sec. 3 T.4N. R.1W. (Heyl et al., 1959).
— Crystals are reported from the Crow Branch Mine (NE NW Sec. 3 T.4N. R.1W.) (Hobbs, 1895). Found near Arthur at the Last Chance Mine (NE NW Sec. 3 T.4N. R1W.) and at the Washburn Mine (SW SE SE Sec 34 T.5N R.1W.) (Taylor, 1964).
IOWA COUNTY: Fairly widespread in the zinc-lead ores of the Upper Mississippi Valley zinc-lead district. Many of the mines listed under galena and sphalerite in this county are also baryte localities. Some of the more important occurrences in the county are listed below.
— Found in the Mineral Point subdistrict often as white radiating bladed sheaves associated with galena (Raasch, 1924). Notable localities are the Hoare Mine (SW Sec. 6 T.4N. R.3E.) and the Hazel Patch and Western Mine (center of sec. 26 T.5N. R.2E.) (Heyl et al., 1959). Also noted by Strong (1877) at the Bennett and Co. mine in NE NE sec. 1 T.4N. R.2E.
— Hobbs (1895) describes baryte crystals collected at the Linden Mine as light gray to brown, up to 1.5 cm. in length elongated parallel to the b axis and dominated by the basal pinacoid, second and third order prisms.
— Found at the O.P. David Mine, S 1/2 Sec. 30 T.6N. R.1E., west of Cobb (Heyl et al., 1959).
— Roadcuts made during the 2002-2003 expansion of highway 151 near Mineral Point produced masses and crystals of bladed baryte with sphalerite, galena and marcasite.
IRON COUNTY: White to pink crystals and cleavable masses are found in veins and cavities associated with manganese minerals, such as rhodochrosite and calcite, in the iron formation at the Montreal Mine, Montreal (Dickey, 1938). LaBerge (1984) describes these vugs as “spectacular”, noting in addition a wide range of associated minerals such as gypsum, magnetite, quartz, hematite, goethite and psilomelane. Reported habits include: thick tabular xls. sometimes in parallel growths; sheaves and sprays; flattened “poker chips”; rosettes, and reticulated xls. The colors can be white, red, orange, blue or pink. Baryte also occurs at nearby the Ottawa Mine, Hurley in blue, brown or orange single crystals and rosettes with faces up to 5 cm long.
KENOSHA COUNTY: Baryte occurs in a subsurface, diamond-bearing lamprophyre diatreme, discovered within the outskirts of Kenosha (Carlson and Adams, 1997.).
LAFAYETTE COUNTY: Fairly widespread in the zinc-lead ores of the Upper Mississippi Valley zinc-lead district. Many of the mines listed under galena and sphalerite in this county are also baryte localities. Some of the more important occurrences in the county are listed below.
— Common in many of the mines in the Benton-New Diggings area in T.1N. R.1E. Some of the important baryte localities include the Ewing and Cook Mine (NE NW Sec. 12 ), the Weiskircher Mine (NW SE SW Sec. 12), and the Imperial Mine (E 1/2 Sec. 12), and the Farrey Mine (NW Sec. 14) (Heyl et. al., 1959). Zimmermann (1969) finds barite at the Teasdale Mine (sec. 21) and the Temperley Incline of the Thompson-Temperley ore body (sec. 28).
— Common in many of the mines in the New Diggings-Shullsburg area in T.1N. R.2E. Some of the important baryte localities are the Coughlin Mine (NW SE Sec. 4), the Little Bennie Mine (SW SW Sec. 4), the De Rocher Mine (NE NE Sec. 5), the Old Mulcahy Mine (SW NE Sec. 9), the South Hayden ore body at the Calumet and Hecla Mine (Sec. 22), and at the Crawhall mine (SW NW Sec. 30) where large leached casts of baryte were found (Heyl et. al., 1959). Mullens (1964) describes barite occurring at the Blackstone Mine (sec. 28) as veins up to 9 cm. thick spaced from 1 to 12 cm. apart. Also at Blackstone Mine in white sheaf cluster with sphalerite, galena, and marcasite.
— Relatively abundant in the Meeker’s Grove subdistrict, T.2N. R.1E. where it is found at a number of old zinc-lead mines. Some important occurrences are the Connecting Link Mine (E 1/2 SE 1/4 Sec. 16), the Gritty Six Mine (SW , Sec. 21), the Raisbeck Mine associated with galena crystals in flats and veins nearly 2 meters thick (S 1/2 Sec. 21), the Trego-Anthony Mine (N 1/2 SE 1/4 Sec. 21), the Roosevelt Mine (NE SW Sec. 28) and the James Mine (NW Sec. 28). (Heyl et. al., 1959). The Porter Mine (NE NW Sec. 34 and NE NE Sec. 33) was specifically worked for baryte. The baryte at the Porter Mine is associated with galena and described as coarse white crystals and masses. (Brobst and Heyl, 1976).
— Found at the Paquette Mine (SE SW Sec. 32 T.2N. R.2E.) near Shullsburg. (Heyl et al., 1959).
— Found as brown bladed crystals up to 4-5 cm. in length from mines near Belmont in T.3N. R.1E. (Hobbs, 1905).
— Found near Calamine in SW Sec. 24 T.3N. R.2E. at the Southwestern Wisconsin Mine and the M.C. Mine as white platy crystals (Heyl et al., 1959; Klemic and West, 1964).
—Found near NE SW Sec. 22 T.4N. R.1E. near Leslie. (Heyl et al., 1959).
MARATHON COUNTY: Baryte as “crumbly white masses up to 4 mm. across associated with anhydrite” is found in vugs in the pegmatites of the Wausau pluton (Falster, 1987).
— Baryte occurs as clear platey micro-crystals associated with cassiterite and other rare minerals at the McGuire Pit , just west of the LaDick east “rotten granite” quarries, west of Wausau (Buchholz et al., 2004).
MILWAUKEE COUNTY: Complex bladed groups of tabular white and pale blue baryte xls – up to 14 cm with quartz, calcite at Esterbrook Park (Bagrowski, 1940).
RACINE COUNTY: White and yellow baryte occurs with pyrtie at the Vulcan Materials Quarry (Ives quarry) north of Racine.
WOOD COUNTY: Baryte occurs as tiny xls. in vugs in quartz veins within a chloritized zone in granite at the Cepress quarry (sec. 11 T.27N. R.2E.) (Tom Buccholz, pers. com.).
—Baryte is found as microscope crystals sprays in miarolitic cavities in granite in the Haske quarry, sec. 25 T.24N R.2E. (Tom Buchholz, pers. com.).