Properties of Sodalite

Sodalite is a blue-colored mineral that typically forms in igneous rocks. It belongs to the group of feldspathoid minerals and is composed of sodium aluminum silicate chloride.

Image of sodalite mineral — Credit: James St. John, CC BY 2.0, via Wikimedia Commons

The following table provides a comprehensive list of sodalite properties in both SI and US customary/Imperial units at normal temperature and pressure (NTP).

Note: click on the icon to switch between Metric and Imperial units.

Table of Sodalite Properties
Physical Properties	Metric
Chemical Formula	Na₈(Al₆Si₆O₂₄)Cl₂
Molar Mass	933.76 g/mol
Crystal System	Cubic
Mohs Hardness	5.5 - 6
Density	2270 - 2330 kg/m³
Color	Azure blue, white, yellow, pale pink, colorless, gray, or green
Diaphaneity	Transparent to translucent
Luster	Vitreous (glassy), greasy
Cleavage	(110) good
Fracture	Conchoidal
Streak	White
Optical Properties	Metric
Refractive Index (n_D)	1.483 - 1.487

Note: unless stated otherwise, all values are taken at room temperature (approximately 20°C or 68°F) and 1 atm pressure. (1 atm = 101,325 Pa)

References: 1) Cardarelli, François. Materials Handbook: A Concise Desktop Reference. Switzerland: Springer International Publishing, 2018. 2) CRC Handbook of Chemistry and Physics, 97th Edition. United Kingdom: CRC Press, 2016-2017.