Where is Sodalite Syenite found?
Sodalite (Na8(Al6Si6O24)Cl2) in Syenite
Got a photo? Identify rocks instantly with the Rockby app
Open the appSodalite Syenite occurs in specific geological environments. Knowing where to look, and in what kind of rock, is the difference between going home empty-handed and finding a great specimen.
Where to find Sodalite Syenite
Bancroft, Ontario, Canada
Known for excellent occurrences of sodalite in nepheline syenite, particularly in the Princess Sodalite Mine area. The sodalite here is often a rich royal blue.
Litchfield, Maine, USA
Historical locality for sodalite-bearing syenites.
Kola Peninsula, Russia
Numerous alkaline massifs, such as the Khibiny and Lovozero massifs, contain extensive occurrences of sodalite-bearing rocks, including syenites and nepheline syenites.
Ilimaussaq Complex, Greenland
A large alkaline intrusive complex famous for its rare minerals, including sodalite in various alkaline rocks.
Brazil
Various localities, particularly in Bahia and Minas Gerais, produce sodalite, sometimes found within syenitic or related alkaline rocks.
Namibia
Certain alkaline complexes contain sodalite-rich rocks.
Collecting tips
- Look for Blue Coloration. The most obvious indicator is the distinctive blue color of sodalite within a lighter-colored, coarse-grained igneous rock matrix.
- Check for Fluorescence. Some sodalite, particularly hackmanite (a variety of sodalite), exhibits tenebrescence (photochromism) and/or fluorescence under UV light, often turning pink or orange. This can be a useful diagnostic tool.
- Acid Test (Caution Advised). Sodalite reacts slowly with hydrochloric acid (HCl), forming a gelatinous silica residue and releasing a faint odor of hydrogen sulfide if sulfur is present as an impurity. This test should only be performed by experienced individuals with appropriate safety precautions, as HCl is corrosive.
- Examine Texture. Confirm the phaneritic (coarse-grained) texture characteristic of intrusive igneous rocks. Look for interlocking crystals.
- Associated Minerals. Look for other minerals typical of alkaline rocks, such as nepheline (greasy luster, often grey), alkali feldspars (pink, white, grey), and dark amphiboles or biotite.
Quick Check
- Color:
- Blue (sodalite) within a light-colored (pink, white, grey) matrix.
- Luster:
- Vitreous to greasy (sodalite), vitreous (feldspar).
- Streak:
- White (sodalite).
Explore Sodalite Syenite
Identify rocks anywhere
Free on iOS, Android, and Web. Photo identification, full database, and your personal collection.