Root Beer Fluorite, Graymont Quarry, Genoa, Ohio

This large specimen from the Graymont Quarry in Genoa, Ohio features colorless, transparent fluorite cubes with root beer brown, zoned centers on a light grey limestone matrix. There are also some white bladed celestine crystals present. As shown in the photographs below, the fluorite is brightly fluorescent and phosphorescent under UV. The fluorescent response is activated by organic inclusions in the fluorite crystals. The size of this specimen is 105 x 71 x 67 mm, and it weighs 477 grams.

The Graymont Quarry (aka Graymont Dolime Quarry, Genoa Quarry) is a well-known producer of beautiful fluorite specimens. This active quarry has been in operation since the late 1800's, and produces lime products and construction aggregate.

Bright white, zoned fluorescence is seen in the fluorite cubes when viewed under short wave UV (254 nm). Note that the limestone matrix is also moderately fluorescent.

Following exposure to short wave UV (254 nm), pale blue/green phosphorescence is seen.

As is typical for root beer fluorite from northwest Ohio, this specimen shows its brightest fluorescent response under long wave UV (365 nm). Note that the response is warmer than seen under short wave UV.

Pale yellow phosphorescence is seen following exposure to long wave UV (365 nm).

Same specimen shown under visible light. Colorless, transparent fluorite cubes with root beer brown, zoned centers on a light grey limestone matrix. Also some white bladed crystals of celestine.

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