Slight white or light yellow,sweet and toxic powder with specific gravity of6.1 and refractive index 2.25.It can not dissolve in water, but can dissolve in hydrochloric acid and nitric acid.It turns to gray & black at 200℃ it turns to yellow at 450℃,and it has good deductibility.It is antioxidant it has the excellent performance of resistance to ultraviolet raycold and aging.