Potassic magnesio-arfvedsonite
Chemical formula: KNa<sub>2</sub>Mg<sub>4</sub>Fe<sup>3+</sup>Si<sub>8</sub>O<sub>22</sub>(OH)<sub>2</sub>
Cabinet No. 40
Chemical formula: KNa<sub>2</sub>Mg<sub>4</sub>Fe<sup>3+</sup>Si<sub>8</sub>O<sub>22</sub>(OH)<sub>2</sub>