The Types And Characteristics Of Nephrite Secondary Mineral

Nephrite is also called Hetian Yu, is circulated as a medium of cultural heritage of the Chinese nation for thousands of years, its long history was accompanied with the development of the whole national history. In accordance with the occurrence of different materials, Nephrite is divided into nephrite gravels, primary nephrite and slope jade. Due to a long process of epigenetic changes, nephrite gravels is usually better, and colors of Nephrite gravels cuticles is bright. Nephrite gravels has more artistic value after skillfully carved, so Nephrite gravels with cuticles is popular in the market. But for true and false identification of the material has not a mature theory to guide practice, investigations of the secondary changes of Nephrite and secondary minerals are especially weak. This research aims at this problem, secondary minerals of Nephrite are studied systematically.The conclusion is theExperiments on large numbers of Nephrite macroscopic observation and microscopic observation of sample specimens, appearance characteristics of the primary nephrite and the nephrite gravels and artificial coloring nephrite gravels were compared, respectively.Then selected samples are cut to make translucent slices, they were observed by polarizing microscope. The structure and existing form of the secondary minerals are studied. Found secondary replacement mainly happens on the epidermis, fractures and micro fractures, as well as a part of the mineral grains gaps in combination with not close enough.fractures and micro fractures provides channels for secondary replacement. Secondary mineral aggregate patterns are usually scattered along the fissure vein, or keep the form of original mineral.Using multiple modern testing technology such as infrared spectroscopy, X- ray powder diffraction and Raman spectroscopy, the mineral compositions of discovered secondary minerals is analyzed.The conclusion of a series experimental is that the diopside was replaced,secondary minerals of tremolite is later than nephrite(the main mineral is tremolite contain diopside etc.)and loose texture, is also a kind of secondary minerals and there are more common, in primary nephrite and nephrite gravels all can appear.The nephrite gravels of cot and its nearby there are some secondary minerals such as Antigorite,Chlorite,Talc,Calcite,etc.Antigorite,Chlorite,Talc,Calcite,etc. secondary mineral combinations is the typomorphic mineral assemblage of the nephrite gravels.