Betpakdalite-CaMg
Chemical formula: [Ca<sub>2</sub>(H<sub>2</sub>O)<sub>17</sub>Mg(H<sub>2</sub>O)<sub>6</sub>][Mo<sup>6+</sup><sub>8</sub>As<sup>5+</sup><sub>2</sub>Fe<sup>3+</sup><sub>3</sub>O<sub>36</sub>(OH)]
Cabinet No. 40
Chemical formula: [Ca<sub>2</sub>(H<sub>2</sub>O)<sub>17</sub>Mg(H<sub>2</sub>O)<sub>6</sub>][Mo<sup>6+</sup><sub>8</sub>As<sup>5+</sup><sub>2</sub>Fe<sup>3+</sup><sub>3</sub>O<sub>36</sub>(OH)]