my-server
← Wiki

Ferri-obertiite

Ferri-obertiite is an amphibole group mineral that was formally approved by the International Mineralogical Association in 2015. It has the chemical formula Na(Na<sub>2</sub>)(Mg<sub>3</sub>Fe<sup>3+</sup>Ti)(Si<sub>8</sub>O<sub>22</sub>)O<sub>2</sub>.

Ferri-obertiite is highly sodic and is especially characterized in the presence of oxygen instead of a hydroxy group or fluorine at the W site, which compensates for the relatively high positive charge due to the dominance of ferric iron and presence of titanium. Similar to many other amphiboles, ferri-obertiite is monoclinic with space group C2/m.

The name honors professor Roberta Oberti of the University of Pavia, Italy.

References