Fluorite with Chalcopyrite

Minerva No. 1 Mine, Ozark-Mahoning group, Cave-In-Rock Mining Sub-District, Hardin County, Illinois, USA

6.9 x 6.4 x 4.9 cm

ex. Barton Friedman

This is an “old find” from the collection of Barton Friedman from Minerva No. 1. featuring well formed glassy Fluorite cubes neatly clustered together in a compact and showy display. With a rich yellow filling the core of the specimen, each of the crystals are highlighted by deep purple zones. The specimen is accompanied by small inclusions of Chalcopyrite, along with minor amounts of a darker, slightly metallic material lightly coating the bottom of the display. Many of the crystal faces show some degree of stepped growth at their center, which is a commonly seen trait among Fluorites from this region; however, the Fluorite does have a number of completely smooth faces that better convey the piece's vitreous luster.