The Guangning jade is a precious type of Chinese jades

which is found in Guangning county

Guangdong province. Four types of different colored jade stones were sampled from a jade deposit. Their mineralogical characteristics were analyzed using XPD

SEM

DTA

IR and EMPA techniques. The Guangning jade is mainly composed of 2M1 sericite

and secondly chlorite. Both XPD and IR results indicate daunialite does not exist in the crystal structure of sericite. The analysis of DTG shows that the dehydroxylation tempreture of samples is beyond 600 ℃

which is different from hydromica. The microtexture of sericite shows flakeshaped

and the minerals arrange along the longaxis of crystal

interleaved by each other

showing overlapped and flake interleaved microstructure. The EMPA suggests that sericite is rich in Si、K、Al and Cr. Those rich in Cr can be grouped into Crbearing sericite.