What is "marialite"

n. (context mineralogy English) A tetragonal-dipyramidal mineral containing aluminum, chlorine, oxygen, silicon, and sodium.

Marialite is a silicate mineral with a chemical composition of NaAlSiOCl if a pure endmember or Na(AlSiO)(Cl,CO,SO) with increasing meionite content. Marialite is a member of the scapolite group and a solid solution exists between marialite and meionite, the calcium endmember. It is a rare mineral usually used as a collector's stone. It has a very rare but attractive gemstones and cat's eye.