Fluorescent Mineral Database

A new secret project! Trying to create a nice Fluorescent Mineral Database (FMDB), which would be searchable by mineral, locality, and luminescence properties. Also making it easy for people to contribute with their own specimens!

Fluorite and Celestine - Stoneco White Rock Quarry, Clay Center, Ohio

Contributed by: Chris Clemens
Date: Apr 25th, 2026
Locality: Stoneco White Rock Quarry, Clay Center, Allen Township, Ottawa County, Ohio, USA (See on Mindat)
Size: 50 x 28 x 65 mm

Description:
Root beer-colored fluorite cubes with white translucent blades of celestine, from the Stoneco White Rock Quarry, Clay Center, Ottawa County, Ohio. Fluorite specimens from Clay Center, Ohio, are notable for their bright white, zoned fluorescence under longwave UV. Also impressive under shortwave UV, the fluorite shows a cooler white, and slightly dimmer fluorescent response. This material is also phosphorescent under both wavelengths, showing a white glow after shortwave UV, and green after longwave. The fluorescence in the Clay Center fluorites is likely due to the presence of an organic activator.

Originally posted by Chris Clemens on Nature's Rainbows in 2016.

Fluorescence under longwave UV light.
Fluorescence under longwave UV light.
Afterglow after exposure to longwave UV light.
Afterglow after exposure to longwave UV light.
Fluorescence under shortwave UV light.
Fluorescence under shortwave UV light.
Afterglow after exposure to shortwave UV light.
Afterglow after exposure to shortwave UV light.
Normal light.
Normal light.

Summary of luminescence responses:

Fluorite (Mindat) (RRUFF)

  • Fluorescence under Longwave (365nm LED) UV light: White
  • Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: White
  • Afterglow after exposure to Longwave (365nm LED) UV light: Green
  • Afterglow after exposure to Shortwave (254nm Lamp/Mercury) UV light: Blue

FMDB Home Page
Submit a new specimen!
My Collection