GAYLUSSITE
Class : Carbonates, nitrates, borates
Subclass : Hydrated carbonates
Crystal system : Monoclinic
Chemistry : Na2Ca(CO3)2 5H2O
Rarity : Quite common
Gaylussite is a hydrated carbonate formed by evaporation of salt lakes. In its deposits it is associated with thermonatrite, trona, calcite and many other carbonates. It was named in honor of the French physicist and chemist Louis Joseph Gay-Lussac who established the law of gas expansion, the laws of the combination of gases in volume and who discovered boron. Gaylussite is a mineral that occurs in crystals that are often flattened and elongated, with beveled ends and usually uneven faces. It is colorless or grayish-white in color, sometimes yellowish. Usually translucent, gaylussite becomes opaque and whitens in the air ; furthermore it easily alters into calcite. It is a sodium ore.
Main photo : Gaylussite from Taboos-nor, Gobi Desert, Mongolia © Joan Rosell
Gaylussite in the World
Twinning
No twin known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 2.5
Density : 1.99
Fracture : Conchoidal
Streak : Gray-white
TP : Translucent to transparent
RI : 1.444 to 1.523
Birefringence : 0.079
Optical character : Biaxial -
Pleochroism : None
Fluorescence : None
Solubility : Nitric acid and hydrochloric acid
Magnetism : None
Radioactivity : None