Yttrofluorite from Norway
Contributed by: Michael Crawford
Date: Jul 7th, 2025
Locality: Innhavet, Hamarøy, Nordland, Norway (See on Mindat)
Size: 9 x 14
Description:
A yttrofluorite specimen from Innhavet, Drag, Nordland, Norway is a fluorite variety where yttrium (Y3+) replaces some calcium (Ca2+), altering its structure ((Ca1-xYx)F2+x). The shortwave, midwave and longwave emission spectra show multiple peaks due to rare earth element activation. The brightest fluorescence occurs in the ultraviolet region under shortwave illumination. The shortwave emission spectrum has a maximum at 310 nm in the ultraviolet range caused by yttrium substitution, while visible peaks are linked to other REEs like dysprosium and terbium. Fluorescence color varies with the wavelength of UV illumination. Terbium activated fluorescence dominates the longwave response and produces a green color. No REE dominates the activation of visible fluorescence under midwave and shortwave illumination and result is a mix of colors to produce white.
Summary of luminescence responses:
Yttrofluorite (Mindat) (RRUFF)
- Fluorescence under Longwave (365nm LED) UV light: Green
- Fluorescence under Midwave (305nm LED) UV light: White
- Fluorescence under Shortwave (255nm LED) UV light: White