Fluorite from Bluffton, Ohio

Contributed by: Chris Clemens
minID: U7Q-RC5
Date: Apr 22nd, 2026
Locality: Bluffton, Richland Township, Allen County, Ohio, USA (See on Mindat)
Size: 58 x 31 x 84 mm
Weight: 131 g

Description:
The Midwest is host to a variety of locations that have produced unique fluorite specimens that do not show the typical deep blue, fluorescent response under UV. The fluorescence in these fluorites is activated by organic impurities that show a cream to white response, and they are also generally strongly phosphorescent. This is one such specimen. It is from the Bluffton Stone Co. Quarry, in Bluffton, Allen Co., Ohio, and consists of two generations of fluorite crystals; an initial growth of brown/yellow cubes and secondary purple fluorite perched on the older cubes, all on a buff-colored dolomite matrix. Under UV, the older brown/yellow cubes show a bright cream white to yellow/white fluorescence, while the younger purple cubes show only a dim blue/purple response. The fluorite is also phosphorescent, whitish after short wave UV and strong yellow after long wave. The dolomite matrix is also dimly fluorescent and weakly phosphorescent.

Originally posted by Chris Clemens on Nature's Rainbows in 2018.