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Cancrinite
Chemical Formula	Na6Ca2[(CO3)2|Al6Si6O24]·2H2O
Species	Silicates
Crystal System	Hexagonal
Mohs Scale	5-6
Specific Gravity	2.42-2.51
Color	grey-green, white, yellow, blue, orange, reddish
Streak	white
Luster	Vitreous, Greasy, Pearly
Refractive Index	n = 1.507 - 1.528 n = 1.495 - 1.503
Diaphaneity	Transparent, Translucent
Cleavage	PerfectPerfect on , poor on
Fracture	Irregular/Uneven
Crystal Habit：Rarely as prismatic crystals.
Geological Setting：Primary mineral in alkalic igneous rocks, alteration product of nepheline.

Cancrinite is a complex carbonate and silicate of sodium, calcium and aluminium with the formula Na₆Ca₂[(CO₃)₂|Al₆Si₆O₂₄]·2H₂O. It is classed as a member of the feldspathoid group of minerals; the alkali feldspars that are poor in silica. Yellow, orange, pink, white or even blue, it has a vitreous or pearly lustre; a hardness of 5-6 and an uneven conchoidal fracture. It is unusual among the silicate minerals in that it will effervesce with hydrochloric acid due to the associated carbonate ions.

Found originally in 1839 in the Ural Mountains, it is named after Georg von Cancrin, a Russian minister of finance.