Quartz and Calcite on Sphalerite, Sub-Rosiclare Level, W. L. Davis/Deardorff Mine, Ozark-Mahoning Company, Cave-in-Rock District, Southern Illinois, Mined c. 1960's, ex. Roy Smith Collection, Medium Cabinet 5.5 x 6.0 x 8.3 cm, $125. Online Dec. 14
Combination of exceptionally high luster "Black Jack" sphalerite and vitreous quartz. A hallmark specimen from the famous W. L. Davis/Deardorff Mine. Note: Small cluster of pale yellow calcite as typical association from orebody.