Gemmological Characteristic of Serpentine Jade ("Rehe Jade") from Chengde, Hebei Province

"Rehe jade", a new variety of serpentine jade, was discovered at the junction place between the Kuancheng Manzu Autonomous County, Chengde City, Hebei Province and Lingyuan City, Liaoning Province. In the paper, a systematic investigation with the help of polarizing microscope observation, X-ray powder diffraction analysis and infrared spectroscopic techniques for the "Rehe jade" was performed. The results showed that the "Rehe jade" mainly consists of clinochrysotile with micro-fiberous and interwoven structures, and minor components are diopside and calcite. The major difference between "Rehe jade" and other serpentine jades is its red and yellow colour, which is caused by Fe element. It was suggested that the "Rehe jade" from Hebei Province is formed by the contact metasomatism between SiO₂-rich magmatic rock and dolomitic limestone. It is a high-quality jade resource with high economic development and utilization value.