Fluorite from Pakistan
Contributed by: Michael Crawford
Date: Jul 8th, 2025
Locality: Skardu Area, Gilgit-Baltistan, Pakistan (See on Mindat)
Size: 8 x 12 cm
Description:
Large green fluorite crystals on a feldspar matrix. The specimen comes from Skardu, Pakistan. The specimen fluoresces blue green under longwave and shortwave UV illumination. It has bright blue-green afterglow after exposure to all wavelengths of UV light. According to the emission spectra, the fluorescence is activated by a mix of rare earth elements (REE’s) that replace calcium in the fluorite structure. It appears that europium (Eu3+) that commonly activates the blue fluorescence in many fluorite specimens is absent in this specimen. The spectra indicate that dysprosium (Dy3+), terbium (Tb3+), erbium (Er3+), gadolinium (Gd3+) and yttrium (Y 3+) activate various fluorescent peaks that create the blue green fluorescence.
Summary of luminescence responses:
Fluorite (Mindat) (RRUFF)
- Fluorescence under Longwave (365nm LED) UV light: Green
- Fluorescence under Shortwave (255nm LED) UV light: Green
- Afterglow after exposure to Longwave (365nm LED) UV light: Green
- Afterglow after exposure to Shortwave (255nm LED) UV light: Green