Multi-Colored Sphalerite, Balmat No. 4 Mine, Balmat, New York
Large, triangular-shaped piece of metallic grey colored sphalerite/zinc ore with brassy grains of an unidentified sulfide mineral (pyrite or chalcopyrite), from the ZCA Mine No. 4 (now called the Empire State No. 4 Mine), Balmat, St. Lawrence Co., New York. This specimen shows a beautiful, moderately bright, multi-colored fluorescent response under long and short wave UV. This material is sometimes referred to as "birdseye sphalerite" or "birdseye ore." The size of this specimen is 15.8 x 11.6 x 4.25 cm and it weighs 658 grams.
Fluorescence under long wave UV (365 nm). The "birdseye" pattern can be seen toward the center and lower left of the specimen.
Following exposure to long wave UV, bright pink and green phosphorescence/afterglow is seen.
Fluorescence under short wave UV (254 nm) reveals a response consisting of reds, orange, pink, brown and minor green.
Green and red phosphorescence is seen following exposure to short wave UV (254 nm).
Under visible light, this specimen is not particularly attractive and gives no indication as to its beautiful fluorescent response under long wave UV.