Tags: Chemical Substance, Mineral.
Lawsonite is a hydrous calcium aluminium sorosilicate mineral with formula CaAl2Si2O7(OH)2·H2O. Lawsonite crystallizes in the orthorhombic system in prismatic often tabular crystals. Crystal twinning is common. It forms transparent to translucent colorless white and bluish to pinkish grey glassy to greasy crystals. Refractive indices are nα=1.665 nβ=1.672 – 1.676 and nγ=1.684 – 1.686.
