Witherite - Minerva No 1 Mine, Hardin County, Illinois

I love mineral specimens that tell a story like this one. In this case, we have a very large witherite crystal that experienced a tectonic break during growth. The break is filled with purple fluorite and white calcite. The tear separated the witherite into two halves which may have continued to grow, but at slightly different angles. The tear through the witherite is not complete and almost appears to have healed itself near the large termination. It almost appears that it sutured together with stitches! While the tear is interesting geologically, the witherite itself is a beast measuring 6.5 cm x 6.5 cm x 5 cm. With barium the key element in this mineral, it is very hefty at this size. The crystal is complete with deep colour and terrific luster. Fluorescence is very nice under short wave UV light. The Minerva No 1 Mine is arguably the best locality for the species worldwide and this piece is no exception. Ex Bill Rouslin collection. From: Minerva No 1 Mine, Cave-in-Rock district, Hardin County, Illinois.

Mineral: Witherite
Locality: Minerva No. 1 Mine, Cave-in-Rock District, Hardin County, Illinois, USA
Crystal System: Orthorhombic
Mineral Class: Carbonates
Short Wave Ultraviolet response: Bluish-white cream
Provenance: Ex Bill Rouslin Collection
Dimensions: 6.5 × 6.5 × 5 cm