Si
O
Ba
Ce
Fe
Ti
H
F

Joaquinite

Joaquinite is a cyclosilicate with 4-membered silica rings. The individual silica rings are bonded together by titanium (Ti) and iron (Fe), while barium (Ba) and cerium (Ce) are the charge-balancing cations. Water is also present in the structure. Joaquinite has a monoclinic crystal system.

Distribution

Joaquinite was discovered in California. It is rather rare, but is a good example of a 4-membered cyclosilicate structure.

Dowty, E. 1975. Crystal structure of joaquinite. American Mineralogist 60:872-878.