Sodalite Varieties
Greenland sodalite is found throughout the various complexes in large quantities. Much of it is the typical gray or yellow variety, and almost all of it fluoresces a bright orange. Walking along the mountain trials at night is much like night prospecting in the Franklin NJ dumps - but instead of the ever present orange glow from calcite, it’s an orange glow from sodalite.
Certain areas are known for high-quality, vibrantly colored sodalite. The Gronnedal-Ika Complex (near the Arsuk Fjord) contains vein fillings and dissemination of ultramarine-blue sodalite. The color is intense and well suited for polishing. Within the Ilimaussaq Complex there is an area which yields a highly tenebrescent green sodalite (variety hackmanite), mixed with brightly fluorescent green uranyl activated fluorescing mineral. One type is so deeply tenebrescent we have nicknamed it “Chameleon Sodalite”.
Sodalite ranges in (daylight) color from blue, white, pink, gray, green, yellow and most (to date) fluoresce a brilliant orange under long wave UV. SW fluorescence varies depending on the type and locale, as does tenebrescence. The tenebrescent qualities of Greenland sodalite are perhaps one of the more technically interesting aspects of this mineral. The Tenebrescence Overview provides more information and observations on tenebrescense
Chemical formula: Na8Al6Si6O24Cl2. Hardness = 6.0, Density = 2.29
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