Evaporite minerals are geologically important because they clearly are related to the environmental conditions that existed at the time of their deposition, namely arid. They also can be easily recrystallized in laboratories in order to confirm their specific characteristics of formation. This is an indication of a change in their respective crystal structures. The two are best distinguished by their crystal habits in which pirssonite has a distinctive tabular diamond-shaped crystal form. Pirssonite can lose its water molecules and specimens should be stored in a sealed container.
Color is colorless, white or yellowish.
Luster is vitreous. Crystals are transparent to translucent. Crystal System is orthorhombic. Fracture is conchoidal. Streak is white.