Chlorophane, Sphalerite, Fluorapatite, Willemite from Franklin, New Jersey

This is a beautiful 4-color, mixed mineral, fluorescent specimen from the Franklin Mine, Franklin, New Jersey. The primary component is chlorophane, an amber/brown colored variety of fluorite that shows a teal blue/green fluorescent response and is thermoluminescent (emits light when heated). This rock also contains sphalerite, fluorapatite and willemite. Under short wave UV the chlorophane fluoresces teal blue/green, the sphalerite pink, the fluorapatite orange, and the willemite classic bright green. The chlorophane is also strongly phosphorescent after exposure to short wave UV. Under mid wave UV the chlorophane shows a similar, but dimmer teal response, while the sphalerite (pink) and fluorapatite (orange) both fluoresce more brightly. Under long wave UV the chlorophane again shows a dim teal-colored response, and the sphalerite fluoresces a violet color. Very little of the orange fluorescing fluorapatite can be seen under long wave. The size of this specimen is 41 x 27 x 19 mm.

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