Mineral Specimen #4382 Aragonite on Sphalerite with Minor Fluorite
Hardin Co., Illinois
Ex. A. Neely, 1960s
White, crudely formed, aggregates of Aragonite crystals have grown on the terminations of Sphalerite crystals which are a dark brown almost black color with reddish highlights. There is a very unusual, oval shaped cast in the Sphalerite on the back side of the specimen. The Aragonite has no luster but the Sphalerite has a nice glossy almost greasy looking luster. The oval cast has a very high luster. Aragonite specimens from Hardin County are not common and are seldom available.
Flaws: The Sphalerite is cleaved below the Argonite on the side with the unusual cast.