Fluorescent Mineral Database

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Selenite Twinned Crystals, Willow Creek Location, near Nanton, Alberta, Canada

Contributed by: Chris Clemens
Date: Apr 22nd, 2026
Locality: Willow Creek, Nanton, Alberta, Canada (See on Mindat)
Size: 29 x 19 x 41 mm
Weight: 15 g

Description:
Twinned gypsum var. selenite crystals from the Willow Creek location, near Nanton, Alberta, Canada. These crystals show a very unique fluorescent response under UV light, producing a bright hourglass-shaped area of zonal fluorescence that is characteristic for selenite crystals from the Willow Creek location. This response is seen under both shortwave and longwave UV. This specimen is also phosphorescent under both wavelengths, most brightly under shortwave.

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

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

Summary of luminescence responses:

Gypsum var. Selenite (Mindat) (RRUFF)

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

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