Mirabilite
Mirabilite, also known as Glauber's salt, is a hydrous sodium sulfate mineral with the chemical formula Na2SO4·10H2O. It is a vitreous, colorless to white monoclinic mineral that forms as an evaporite from sodium sulfate-bearing brines. It is found around saline springs and along saline playa lakes. Associated minerals include gypsum, halite, thenardite, trona, glauberite, and epsomite.
Mirabilite is unstable and quickly dehydrates in dry air, the prismatic crystals turning into a white powder, thenardite. In turn, thenardite can also absorb water and converts to mirabilite.
Mirabilite is used as a purgative in the Traditional Chinese medicine; in Mandarin, it is called máng xiāo. The name 'mirabilite' is based on the phrase "Sal mirabilis" used by Johann Rudolph Glauber when he inadvertently synthesized mirabilite.
