Gem Tenebrescent Sodalite with Ussingite from Greenland

Contributed by: Mark Cole
Date: Apr 14th, 2026
Locality: Tunulliarfik Fjord, Ilímaussaq complex, Kujalleq, Greenland (See on Mindat)
Size: 2.5 x 2 x 4 inches
Weight: 17.1 oz

Description:
Some pieces of sodalite found in the areas around the Tunuliarfik Fjord are very gemmy, and usually nicely tenebrescent. This piece also has areas of bright green fluorescence which are most likely uranyl activated. Areas of ussingite are fluorescent green - quite unusual. Exceptionally bright under longwave.

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

Fluorescence under shortwave UV light.

Fluorescence under longwave UV light.

Tenebrescence after exposure to shortwave UV light.

Normal light.

Summary of luminescence responses:

Sodalite (Mindat) (RRUFF)

• Fluorescence under Longwave (365nm LED) UV light: Orange
• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Orange
• Tenebrescence after exposure to Shortwave (254nm Lamp/Mercury) UV light: Purple