Name: derived from SULFur, plus Greek "hals", salt, alluding to its content of halogens.
Clades: Sulphohalites; Stoichiometric Perovskites Group; Perovskites.
Chemical: Na6(SO4)2FCl.
Colour:Colourless, gray, greenish yellow; colourless in transmitted light.
Lustre: vitreous, Greasy.
Hardness: 3½.
Specific gravity: 2.489 - 2.500.
Crystal system: isometric.