Pyrite, an Iron Sulfide Locality: Ellis County, Texas (probably from the Txi Industries Cement Quarry in Midlothian) Chemical Formula: FeS2 Crystal System: Isometric Specimen size: 3 in x 2.75 in 2.5 in Specimen weight: 103 grams In the Arthur E. Smith Collection, on display at Wheaton College, Wheaton, Illinois.
