gems, jade, fei cui, pyroxene jade, jade testing, jade composite, pressed jade, treated jade, treated fei cui, HPHT

Recycling jade is produced by pressing and sintering powder made from leftover fragments or low-grade natural jadeite sourced from Myanmar. This study examines key factors affecting recycled jade, including color, hardness, and density. Experimental results indicate that weakly magnetic amphibole and iron ore can be removed through magnetic separation, while chromium-rich jadeite achieves uniform color distribution during thermal diffusion. Using spark plasma sintering (SPS), the samples reach 96% of their theoretical density and exhibit hardness exceeding that of natural jadeite. X-ray diffraction (XRD) analysis reveals a phase transition, which can be suppressed through stable pressure and rapid sintering.