蛇紋岩(じゃもんがん)jamongan
マグネシウムとケイ酸を主成分とする蛇紋石を主として構成される岩石。黒・暗緑色を呈し緻密で光沢があり、蛇の皮に似た模様を示すのでこの名がある。装飾用、建材に用いられる。
第75回 正倉院展、2023年
Serpentinite
Ultramafic rocks low in silicon undergo metamorphism when hydrated, a process known as serpentinization. The actual chemistry varies greatly depending on geography and environment. The striped, olive-toned, smooth or scaly appearance gives this stone its name. It is found in most regions through out world.
74th Annual Exhibition of Shōsō-in Treasures, 2022
青斑石鼈合子（中倉50）
Serpentine Stone Lidded Vessel in the Shape of a Chinese Softshell Turtle (Middle Section 50)
Serpentine Stone Lidded Vessel in the Shape of a Chinese Softshell Turtle (Middle Section 50)