Sodalite
Opaque to translucent blue sodium aluminum silicate chloride; chemically distinct from lapis lazuli (a rock containing lazurite, calcite, and pyrite). Strong orange LW fluorescence and low SG (~2.27 vs lapis ~2.75) are the primary field separations. Hackmanite is a pink/colorless variety showing tenebrescence (reversible color change under UV). Typically lacks the gold pyrite flecks present in lapis lazuli.
Physical & Optical Properties
Related: Sodalite Varieties
Key Differentiators
- Hackmanite variety shows strong orange LW fluorescence (tenebrescence); plain sodalite is inert to LW UV — lapis lazuli shows only weak orange LW
- Very low SG (~2.27) — lapis lazuli averages ~2.75
- No pyrite inclusions — lapis almost always has gold pyrite flecks
- Uniform blue — no calcite matrix or lazurite patches
Common Simulants
- Lapis Lazuli: Lapis: SG ~2.75 (much heavier); weak orange LW fluorescence (vs sodalite's strong orange); pyrite inclusions characteristic; aggregate RI spot ~1.50–1.67 range. Lapis is a rock, sodalite is a mineral.
- Blue Glass: Glass: isotropic; conchoidal fracture; gas bubbles under magnification; SG varies; no fluorescence match.
Commonly Confused With
Commonly confused with: Lapis Lazuli.
Treatments
- Waxing / impregnation — surface stabilization (common for opaque stones)
Price Context
Price context is approximate. GemID is not an appraisal tool. Results are indicators, not certified valuations.
About Sodalite
Opaque to translucent blue sodium aluminum silicate chloride; chemically distinct from lapis lazuli (a rock containing lazurite, calcite, and pyrite). Strong orange LW fluorescence and low SG (~2.27 vs lapis ~2.75) are the primary field separations. Hackmanite is a pink/colorless variety showing tenebrescence (reversible color change under UV). Typically lacks the gold pyrite flecks present in lapis lazuli.
Identifying a sodalite? GemID walks through these tests in order — RI, SG, fluorescence, and more.
Try GemID Free →