White hemimoprphite sprays. 79 Mine, Hayden, Arizona. field of view is about 1 cm.
left to right.”
Formula: Zn4Si2O7(OH)2.H2O Orthorhombic
Description: Hemimorphite forms from the breakdown of sphalerite and other zinc minerals. It is common in the oxidized and supergene zones over hydrothermal deposits, where it is associated with smithsonite. Heyl et al. (1959) verified that most of the drab material mined as “drybone” zinc ore contained hemimorphite intergrown with smithsonite so most localities described under smithsonite are also possible sites for hemimorphite.
GRANT COUNTY: Hemimorphite occurs at an adit in the SW Sec. 30 T.3N R.2W near Tennyson, where it is associated with hydrozincite and smithsonite (Heyl et al., 1959).
IOWA COUNTY: Heyl et al. (1959) note hemimorphite as occurring “at Dodgeville” and “at Mifflin”. They also note colorless druses of hemimorphite found on smithsonite from near Mineral Point.
LAFAYETTE COUNTY: Klemic and West (1964) note hemimorphite as a component of drybone ore in both the Calamine and Belmont Quadrangles.
— Hemimorphite was found with calcite and smithsonite at the Ida Blende mine, NW Sec. 15 T.1N R.1E near Benton. (Heyl et at., 1959).
WINNEBAGO COUNTY: Hemimorphite was found with smithsonite, cerussite, sphalerite, cuprite, galena, pyrite, marcasite and calcite at the Lutz quarry, west of Oshkosh along Highway 44. (USGS, 1976).