This fluorite is from the Denton Mine in the Goose Creek Mine Group, Harris Creek Sub-District, Kentucky Fluorspar District, Cave In Rock, Hardin County, Illinois, USA. Seven different minerals have been identified at this mine including fluorite. It is a halide that contains the elements Ca and F. This specimen is a naturally cleaved crystal corner with healed or etched surfaces on the sides and bottom. It has a blue core with multiple purple phantoms towards the surfaces of the crystal. it’s luster is vitreous. It measures 2 3/4 x 1 3/4 x 1 3/8 inches or 70 x 45 x 35 mm.