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!

Gypsum with hourglass from France

Contributed by: Axel Emmermann
minID:
Date: Jan 23rd, 2025
Locality: Seine-et-Marne, Ile-de-France, France (See on Mindat)

Description:
This gypsum is waterclear but contains some humic acids. This organic stuff is accumulated more rapidly in the faster growing direction than in the other ones. It thus forms an hourglass-shaped fluorescence. The fluorescence originates in the pi-bonds in the humic acids.

Fluorescence under longwave UV light.
Fluorescence under longwave UV light.
Normal light.
Normal light.

Summary of luminescence responses:

Gypsum

  • Fluorescence under Longwave (365nm LED) UV light: Blue

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