Sodalite and Natrolite, on Ussingite - Greenland

Contributed by: Mark Cole
Date: Apr 11th, 2026
Locality: Tunulliarfik Fjord, Ilímaussaq complex, Kujalleq, Greenland (See on Mindat)
Size: 2.5 x 2 x 2.5 inches
Weight: 6.3 oz

Description:
Orange fluorescing sodalite atop a non-fluorescent ussingite. The bluish/green mineral on the top is assumed to be natrolite. Areas of the sodalite are tenebrescent. The ussingite is a gem material - which is typically non-fluorescent. When mixed with sodalite it will fluoresce orange and mixed with chkalovite fluoresce green.

Originally posted by Mark Cole on Nature's Rainbows in 2017.

Fluorescence under shortwave UV light.

Fluorescence under longwave UV light.

Tenebrescence after exposure to shortwave UV light.

Normal light.

Summary of luminescence responses:

Natrolite (Mindat) (RRUFF)

• Fluorescence under Shortwave (254nm Lamp/Mercury) UV light: Green

• 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