SC429 - Fluorite, Galena

Locality: Rogerley Mine, Rogerley Quarry, Weardale, County Durham, England, UK (MINDAT)
Size: 6 x 6 x 4 cm - Small cabinet (5-7 cm)
Weight: 188.7 g
minID: HUE-J99

Green, lightly frosted, fluorite cubes up to 14mm by side with a little accompanying black galena. The fluorite is very strongly fluorescent blue under any kind of UV light. Even the sunlight has enough UV to show the blue fluorescence. From the Bluebirds Pocket at the Rogerley Mine, Weardale, UK. Collected between 2013 and 2015.

From the fluorescence spectra, the blue fluorescence is due to europium (peak at 420nm), with a couple of peaks in the UVB (317nm and 337nm), possibly due to cerium.

Photo in normal light and a little bit of 365nm LED UV light.

Left: Fluorescence under 254nm UVC (shortwave) Hg light. Right: normal light.

Comparison between the fluorescence spectra under 275nm, 305nm and 365nm LED excitations.

Fluorescence spectrum under 275nm UVC (shortwave) LED excitation.

Fluorescence spectrum under 305nm UVB (midwave) LED excitation.

Fluorescence spectrum under 365nm UVA (longwave) LED excitation.

Last update: 01 October 2021