Thulium(II) chlorideThulium chloride is an inorganic compound with the chemical formula TmCl2.ProductionThulium chloride can be produced by reducing thulium chloride by thulium metal:Chemical propertiesThulium chloride reacts with water violently, producing hydrogen gas and thulium hydroxide. When thulium chloride first touches water, a light red solution is formed, which fades quickly.