Among the world’s great fluorite localities, Hardin County, Illinois stands apart for its intensely colored, sharply zoned crystals. This impressive 14 cm specimen exemplifies that legacy, thanks to its bold cubic crystal with a golden-yellow core bordered by a narrow indigo zone and an outer rim of electric blue. The geometry is textbook, with defined faces and razor-sharp edges, while delicate calcite crystals frost the cube’s peaks, adding contrast and textural interest. Under light, the fluorite glows with colors remniscent of stained-glass that bring its complex zoning vividly to life.
Formerly part of the esteemed Ross C. Lillie collection, the specimen carries a distinguished provenance. Lillie, a geologist who worked extensively in the southern Illinois fluorspar district, assembled one of the most important and scientifically documented collections of Midwestern fluorite. Combining striking aesthetics, classic crystallography, and notable pedigree, this piece stands as a prime example from one of North America’s most iconic mineral localities.