Beautiful 5-Color Fluorescent Rock from Franklin, New Jersey

This is a beautiful rock from the Franklin mine, Franklin, Sussex County, New Jersey, that shows a spectacular 5-color fluorescent response under short wave UV. This multi-mineral assemblage contains bright yellow fluorescing esperite, bright green willemite, blue fluorescent hardystonite, and minor amounts of red fluorescent calcite and orange clinohedrite. This rock also contains a significant amount of black, non-fluorescent franklinite. This size of this specimen is 64 x 53 x 42 mm, and it weighs 273 grams.

Photograph taken under short wave UV (254nm).

Photograph of same specimen, taken under visible light.

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