Sodalite

Sodalite is a mineral from the tectosilicate group, composed of aluminum and sodium silicate with chlorine (Na₈Al₆Si₆O₂₄Cl₂). It is distinguished by its intense blue to violet-blue hues, often streaked with white calcite veins.

It forms mainly in sodium-rich magmatic rocks, particularly nepheline syenites, where it is often associated with nepheline, calcite, cancrinite, and microcline.