Scalenohedral calcite crystals with minor marcasite and small, brown/amber, cubic fluorite crystals, on limestone matrix. From Pint's Quarry, Raymond, Black Hawk Co., Iowa. This specimen shows a similar fluorescent response under all UV wavelengths- the calcite fluoresces a soft honey-yellow with zones of purple, and the fluorite cubes show a bright cream/white response. Both minerals are also phosphorescent. Specimen size: 66 x 46 x 27 mm, 67 grams.
As shown in the photograph above, taken under long wave UV (365 nm), the calcite provides a soft honey and purple background to brightly fluorescent fluorite cubes.
Same specimen shown under visible light.
Close-up view showing the fluorite cubes under visible light (left) and long wave UV (right).