What is halides in mineralogy ?

Halides : definition

Halides constitute a mineralogical class of about 150 minerals whose common feature is the presence of halogen ions: Cl- (chlorides), Br- (bromides), F- (fluorides) and I- (iodides), bound to cations.

Fluorides are the most abundant mineral species, fluorite (CaF2) being the most common. Chlorides are scarce in terms of number of species, but some are extremely widespread and economically essential, such as halite (NaCl) or sylvite (KCl). Bromides and iodides are much rarer.