SC381 - Scheelite

Locality: Sichuan, China (MINDAT)
Size: 4.5 x 6 x 3.5 cm - Miniature (3-6 cm)
Weight: 77.5 g
minID: 74M-F8R

Octahedral scheelite crystal (15mm) on a flaky muscovite matrix. The scheelite fluoresces bright light blue or white under shortwave UV light. Under longwave (365nm) UV light, the fluorescence is instead yellow/orange, which darkens to a more reddish color under blue laser (405nm). The blue/white fluorescence is due to the intrinsic tungstate groups (WO₄^2-), while the orange fluorescence is due to rare earth elements (REE) substituting the calcium.

Fluorescence under shortwave UV light (254nm Hg light).

Fluorescence under longwave UV light (365nm LED).

Fluorescence under 405nm blue laser, with yellow filter.

Fluorescence spectra after excitation with 275nm UVC LED, 365nm UVA LED and 404nm blue laser. The broad peak centered around 435nm is due to the fluorescence of the tungstate group WO₄^2-. The sharp lines are instead due to a variety of REE emissions.

Last update: 08 June 2021