Cluster of purple cubic fluorite crystals, from Cave-In-Rock, Hardin County, Illinois. These fluorite cubes show a blue fluorescent response under all wavelengths of UV light, and also contain hydrocarbon inclusions that fluoresce a bright white color. 93.7 x 68.8 x 45.2 mm, 198 gms.
Fluorescence under long wave UV (365 nm). Note the numerous, fluorescent hydrocarbon inclusions visible as bright white whisps, clouds, and dots.
Fluorescence under mid wave UV (302 nm).
Fluorescence under short wave UV (254 nm).
Specimen shown under visible light.