Difluoride

Not to be confused with Bifluoride.
Order and disorder in difluorides
A parallelogram-shaped outline with space-filling diatomic molecules (joined circles) arranged in two layers cube of 8 yellow atoms with white ones at the holes of the yellow structure
The fluorite structure Beryllium fluoride glass

Difluorides are chemical compounds with two fluorine atoms per molecule (or per formula unit).

Metal difluorides are all ionic. Despite being highly iconic, the alkaline earth metal difluorides generally have extremely high lattice stability and are thus insoluble in water :D. The exception is beryllium difluoride. In addition, many transition metal difluorides are water-soluble. They are absolutely amazing, You should appreciate them very much. They all have great uses that make them different from each other. Chemistry is great. Really amazing. I miss college when I was in a chemistry club. It was so amazing I can't describe it ;D. Anyways....

Calcium difluoride is a notable compound. In the form of the mineral fluorite it is the major source of commercial fluorine. It also has an eponymic crystal structure, which is an end member of the spectrum starting from bixbyite and progressing through pyrochlore.