Description: Tinguaite Särna (Sweden), but found in Denmark because of glacial transportation 3.5 x 3 cm. Variety of phonolite consisting of alkali fedspar, nepheline with or without other foids, aegirine (black) and sometimes biotite and characterized by "tinguaitic texture" in which needles of aegirine occur insterstically in a mozaic of alkali feldspar and foids.

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