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!

Four Color Fluorescent Specimen from the Purple Passion Mine, Arizona

Contributed by: Michael Crawford
Date: Jun 7th, 2025
Locality: Purple Passion Mine, Morgan Butte, Big Bug Mining District, Bradshaw Mountains (Bradshaw Range), Yavapai County, Arizona, USA (See on Mindat)
Size: 9 x 12 cm

Description:
A four-color fluorescent specimen from the Purple Passion Mine, Yavapai County, Arizona. There are 3 fluorescent minerals in this specimen, fluorite, calcite, and willemite. The willemite has 2 fluorescent colors, green and pale green. Fluorite fluorescence is brightest in LW. The calcite is brightest in MW, and willemite is brightest in SW.

The fourth image shows the emission spectra of the minerals. The fluorite LW emission peaks at 421 nm. This fluorescence is activated by europium replacing calcium. The MW emission spectrum has a broader peak with a maximum at 622 nm, typical of manganese activation. Manganese replaces calcium.
Green fluorescence of willemite is activated by manganese replacing zinc. The peak of the SW emission of the green, fluorescent willemite in this specimen is at 516 nm. The maximum is at a shorter wavelength compared to the peak wavelength (524 nm) of green, fluorescent willemite from Franklin, New Jersey. I do not know the cause of this difference in fluorescence. The specimen also contains pale green, fluorescent willemite. The SW emission spectrum has a very broad peak with a maximum around 480 nm. The activators for this pale green emission have not been described.

The green, fluorescent willemite has long lasting afterglow. The pale green willemite afterglow is highly variable. Some areas have no, or very short-lived afterglow and other areas have longer afterglow, but not as long as the green, fluorescent willemite.

Fluorescence under longwave and shortwave UV light.
Fluorescence under longwave and shortwave UV light.
Fluorescence under longwave UV light.
Fluorescence under longwave UV light.
Fluorescence under shortwave UV light.
Fluorescence under shortwave UV light.
Normal light.
Normal light.
Emission Spectra of Selected Minerals and UV Wavelengths
Emission Spectra of Selected Minerals and UV Wavelengths

Summary of luminescence responses:

Willemite

  • Fluorescence under Shortwave (255nm LED) UV light: Green
  • Fluorescence under Shortwave (255nm LED) UV light: White
  • Afterglow after exposure to Shortwave (255nm LED) UV light: White
Calcite
  • Fluorescence under Shortwave (255nm LED) UV light: Red
  • Fluorescence under Midwave (305nm LED) UV light: Red
Fluorite
  • Fluorescence under Longwave (365nm LED) UV light: Blue

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