BH250-33
Title
BH250-33
Subject
Sodalite
Description
Major Mineral: Sodalite
Minor Minerals: Oxides
BH250-33 is a rock full of Sodalite minerals.
Optical Character: Sodalite is isotropic, belonging to the cubic crystal system. Under plane-polarized light (PPL), it typically appears blue with low relief and generally shows no birefringence. It may exhibit a faint bluish tint in PPL, but remains isotropic under cross-polarized light.
General Information:
Sodalite is a relatively rare, blue-colored tectosilicate mineral within the feldspathoid group. It commonly forms in silica-undersaturated, alkaline igneous rocks such as nephelinite, phonolite, and sodalite syenite. Sodalite typically occurs in environments where quartz is absent or very scarce and is often associated with other feldspathoids like nepheline, leucite, cancrinite, and also with feldspar.
Minor Minerals: Oxides
BH250-33 is a rock full of Sodalite minerals.
Optical Character: Sodalite is isotropic, belonging to the cubic crystal system. Under plane-polarized light (PPL), it typically appears blue with low relief and generally shows no birefringence. It may exhibit a faint bluish tint in PPL, but remains isotropic under cross-polarized light.
General Information:
Sodalite is a relatively rare, blue-colored tectosilicate mineral within the feldspathoid group. It commonly forms in silica-undersaturated, alkaline igneous rocks such as nephelinite, phonolite, and sodalite syenite. Sodalite typically occurs in environments where quartz is absent or very scarce and is often associated with other feldspathoids like nepheline, leucite, cancrinite, and also with feldspar.
Creator
Bereket Haileab
Source
From the rock collection of Bereket Haileab. Sample BH250-33. Housed at Carleton College in Minnesota.
Type
Thin section and hand sample
Relation
Collection
Citation
Bereket Haileab, “BH250-33,” BH250 Mineralogy Teaching Collection, accessed April 25, 2026, https://bereket-haileab.geology.sites.carleton.edu/items/show/37.