Crystals of light grey fluoborite in a groundmass of white Franklin marble, from the Bodnar Quarry, Rudeville, Hardyston Township, Sussex Co., New Jersey. Under short wave UV the fluoborite shows an off-white fluorescent response, and the marble fluoresces dim blue. There is also an unidentified mineral present that fluoresces dim red/orange under short wave UV. The dimensions of this specimen are 6.8 x 4.9 x 4.3 cm.
Fluoborite is a rare hydrothermal mineral which contains fluorine and boron, hence the name “fluo-bor-ite.”