SAM®Magnesium fluoride is an inorganic compound with the formula MgF2, which is a white, fluorescent crystal. It is insoluble in water and alcohol, and soluble in nitric acid. It can be used in ceramics and glass. Magnesium Fluoride is one of the lowest index infrared materials that it is transparent over a wide range of wavelengths, thus is used for optical elements in both the infrared and ultraviolet. It is resistant to thermal and mechanical shock and is twice as hard as Calcium Fluoride.