Arfvedsonite is a sodium amphibole mineral with composition: Na₃(Fe,Mg)₄FeSi₈O₂₂(OH)₂: sodium, iron, magnesium, inosilicate, hydroxide. It is rather rare and occurs in igneous intrusions called nepheline syenites and agpaitic pegmatites. Occurs at Mont Saint-Hilaire, Quebec , Canada, the Ilimaussaq Intrusion, in Southern Greenland, and in pegmatites of the Kola Peninsula, Russia.

Arfvedsonite was named after the Swedish chemist Johan August Arfwedson (1792-1841).

References

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