Green Fluorescing Ussingite with Sodalite - Greenland

Contributed by: Mark Cole
Date: Apr 14th, 2026
Locality: Tunulliarfik Fjord, Ilímaussaq complex, Kujalleq, Greenland (See on Mindat)
Size: 3 x 2 x 4 inches
Weight: 17.6 oz

Description:
Ussingite from Greenland is an oddity in the fluorescent world (to me). It has three states under SW UV - fluorescent orange, fluorescent green, or not fluorescent. It seems that the purest gem quality ussingite is not fluorescent. I believe that the orange fluorescence is caused by an intermixing of sodalite with the ussingite, while the green fluorescence is caused by either a uranyl activator or mixing with a green fluorescing chkalovite (probably also uranyl activated?). In any case, ussingite specimens with this green fluorescence are the least frequently encounter in the Ilimaussaq Complex, and when mixed with other fluorescent colors can be quite striking.

The sodalite on this specimen is nicely tenebrescent, and of course brightly fluorescent under both LW and SW. The bluish/white fluorescence is unknown.

Originally posted by Mark Cole on Nature's Rainbows in 2016.