Strontianite clusters in dolostone, Mackville Quarry, near Appleton, WI.field of view is about 4 cm. (Photo by W. Cordua.)

Formula: SrCO3 Orthorhombic


Strontianite forms white acicular to prismatic crystals. It is found as low temperature hydrothermal mineral and a ground water precipitate, primarily in carbonate sedimentary rocks.

LAFAYETTE COUNTY: Radiating crystals on limestone were reported from the mines of the Shullsburg area. (Raasch, 1924).
— Minute grains of strontianite were observed with barite, sphalerite, pyrite, marcasite, quartz and calcite at the Blackstone Mine (sec. 28 T.1N. R.2E.) near New Diggings (Zimmermann, 1969).

MANITOWOC COUNTY: White to cream fibrous balls and vug fillings of strontianite occur in dolostone in the quarry on the north edge of Valders (Carl Cochrane, 1999, personal communication).

OUTAGAMIE COUNTY: Radiating clusters of white strontianite crystals are found with calcite, marcasite and dolomite in the Mackville Quarry, north of Appleton. The clusters fluoresce blue under both shortwave and longwave UV light (Carl Cochrane, 1999, personal communication).

RACINE COUNTY: Micro. xls. of strontianite occur in vugs in limestone with gypsum, calcite, pyrite, marcasite and sphalerite (Scovil, 1994).