Sodalite
“Royal blue without the royal price”
Sodalite is a deep blue sodium aluminum silicate mineral closely related to lazurite, the main component of lapis lazuli. While less well-known than its cousin, sodalite's rich blue color and white calcite veining make it a popular and more affordable alternative for jewelry and decorative stone.
sodium aluminum silicate chloride (Na₈(Al₆Si₆O₂₄)Cl₂)
Bancroft (Ontario, Canada), Bahia (Brazil), Namibia, Ilímaussaq (Greenland), Vesuvius (Italy), Maine (USA)
5.5-6
A variety called hackmanite exhibits tenebrescence — it changes from pale to deep violet when exposed to UV light, then slowly fades back, a reversible color-change trick unique in the mineral world.
Test Your Knowledge
What is tenebrescence, the optical phenomenon exhibited by hackmanite (a sodalite variety)?
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