Abstract: Along with the steady growth of price of jadeite,there are more and more types of fake gems sold as jadeites.With the help of gem microscope,refractometer,hydrostatic weighing method,infrared spectrometer,the samples resembling black jadeite on appearance are tested.And the results show that the colour of sample is black with light green and glass luster.By magnification,the sample shows column granular structure,the refractive index of sample is 1.71,relative density range of sample is 3.34³.42,and infrared spectrum of sample shows spectrum of zoisite,and its main mineral component is zoisite.Polarizing microscope and X-ray powder diffraction analysis show that this group of black samples are zoisite mineral aggregate.The colour,luster,structure,refractive index,density,infrared spectrum,polarizing microscope and XRD are factors that separate the black samples from black jadeites and confirm the zoisite jade.