Cobalt chloride 2%, aqueous, offers a range of possible applications in scientific laboratories and, where appropriate, in special areas of medical diagnostics. The main components are Aqua bidest and Cobalt(II) chloride hexahydrate. Cobalt(II) chloride hexahydrate, with the chemical formula CoCl2-6H2O, presents as bright red or pink crystals that dissolve readily in water. In aqueous solution, cobalt(II) chloride shows an intense pink to blue coloration, depending on the concentration and hydration state of the cobalt ion. Cobalt(II) chloride hexahydrate is often used in biological studies as a cofactor or enzyme inhibitor. Direct use as a staining agent for tissues and cells in medical diagnostics and histology is less common, due to the toxic properties of cobalt compounds. However, it may find use in specific scientific applications.