Vote for your favorite mineral in #MinCup26! - Sphalerite vs. Anorthite Both zinc ore Sphalerite and calcium plagioclase feldspar Anorthite have perfect cleavage that will split cleanly if you hit them with a hammer, but only one can claim a larger split of your votes!
First described in Dana's System of Minerology 5th edition (1868, p.409) as a pale-yellow zinciferous clay discovered in the upper workings of the Uebberoth Zinc Mine by J. M. Blake. (MSP Newsletter, May 1963, p. 5, PM7) analyzed in 1875 by Prof. W. T. Roepper of Lehigh University. Found in large quantity durring mining operations close to the surface, tonnage of the material was shipped to the Oxide furnaces for recovery of it's zinc content (20-30 percent of Zinc Oxide). ref: B. L. Miller, Lehigh Co., PA; Geol. Surv. Bill. C39, 1941, p. 340)
Habit:
earthy masses, clay-like
Colour:
pale yellow
Luminescent properties:
none
Quality for species:
Excellent - world class for species or very significant. (!!)
Friedensville Mine, Friedensville, Upper Saucon Township, Lehigh County, Pennsylvania, USA