Gemmological Characteristics and Mineral Components of “White Turquoise”

To define the mineral components and structure of the "White turquoise" products in Guangzhou jewelry market,the gemmological,mineralogical and spectral characteristics of the "White turquoise" samples are studied by using the polarizing microscope,XRD and FTIR.The results show that the "White turquoise" sample is porcelain white with dark vein,which resemble turquoise except the colour.Its Mohs hardness is about 5,the density is about 2.95 g/cm³,and RI is 1.68.The results of the comprehensive test indicate that the main mineral component of the sample is magnesite,and the auxiliary minerals are quartz and dolomite,etc.The magnesite is cryptocrystalline texture and massive structure,with quartz veins in it.Recently,the name of "White turquoise" quite easily misguides the customers,so the correct name should be magnesite.