This cluster of multiple crystals of Franklinite features two larger and two medium sized crystals accompanied by multiple small occurrences of Red Willemite which fluoresce green and Sphalerite which fluoresces deep orange. An active-mine piece from early/mid 20th C. from the Franklin Mine, Franklin, NJ. It is the type location for Franklinite. The Franklin mine contained some of the most spectacular geology on Earth, 300 or so different minerals, about 20% of which fluoresce in short or long wave ultraviolet light. This deposit of zinc-iron-manganese ores shaped by Precambrian carbonates are highly metamorphosed and contain minerals in forms that exist almost nowhere else. Franklin Mine, Franklin, NJ, USA. 3.25"" x 2.25" x 2", 13.5 oz.