Cancrinite

tectosilicate

nepheline

Formula: Na,Ca,☐)8(Al6Si6)O24 (CO3,SO4)2.2H2O
Tectosilicate (framework silicate), feldspathoid
Specific gravity:
Hardness: 5 to 6
Streak: White
Colour: Grey-green, white, yellow, blue, orange, reddish
Solubility: It is unusual among the silicate minerals in that it is moderately soluble in hydrochloric acid due to the carbonate ions in its structure.
Environments:

Plutonic igneous environments
Pegmatites
Metamorphic environments

Cancrinite is a primary mineral in some alkaline igneous rocks, including pegmatites in nepheline syenite. It is also an alteration product of nepheline in igneous rocks

Common impurities: Ti,Fe,Mg,K,Cl,S

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