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!

Gibbsite - Wenshan, Yunnan Prov., China

Contributed by: Mark Cole
Date: Apr 7th, 2026
Locality: Wenshan, Yunnan, China (See on Mindat)
Size: 3.5 x 3 x 5 inches
Weight: 14.8 oz

Description:
Gibbsite is a relatively rare aluminum hydroxide. It is composed of two different color phases: a rich blue and a lighter sky blue with individual azure botryoidal spheres around 2.5 mm. Gibbsite from this relatively new find (2012) in Yunnan Province represent some of the most colorful specimens of this uncommon species. It is surprisingly lightweight, and very fragile.

It appears that broken crystals, or ones with thin "shells?" fluoresce blue while most is fluorescent green. Under LW everything shifts to a whitish blue. SW and LW shown, followed by a gallery of closeups, white light pictures and size.

Originally posted by Mark Cole on Nature's Rainbows in 2018.

Fluorescence under shortwave UV light.
Fluorescence under shortwave UV light.
Fluorescence under midwave UV light.
Fluorescence under midwave UV light.
Fluorescence under longwave UV light.
Fluorescence under longwave UV light.
Normal light.
Normal light.
Fluorescence under shortwave UV light. Closeup
Fluorescence under shortwave UV light. Closeup
Normal light. Closeup
Normal light. Closeup

Summary of luminescence responses:

Gibbsite (Mindat) (RRUFF)

  • Fluorescence under Longwave (365nm LED) UV light: Blue
  • Fluorescence under Midwave (305nm Lamp/Mercury) UV light: Green
  • Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Green

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