Sphalerite and Fluorite, Rosiclare Level, Minerva No. 1 Mine, Ozark-Mahoning Company, Cave-in-Rock District, Southern Illinois, Mined c. early 1990's, ex. Roy Smith Collection, Large Cabinet 6.0 x 12.0 x 20.0 cm, $350. Online Dec. 14
NSMW13517
Combination of yellow fluorite and deep brown sphalerite. Even though the specimen is composed predominately of fluorite, this really is a sphalerite specimen with the prominent zinc sulfide crystal measuring 4.5 cm across and shows obvious twinning. Matrix shows concave depressions attributed to dissolution of barite.