Museum Quality Heavily Calcified (surface altered) Jade Yuan. Zhou Dynasty example (1046-256 B.C.). In ancient times the Yuan was probably thrown as a weapon. Eventually the central perforation was cut out to facilitate carrying the disc when it was not in use, and in time the Yuan lost its convex shape and became solely a decorative object.  When the disc became a bracelet, a smooth raised ridge that made the disc more comfortable to wear was added around the central perforation.  This is evidenced not only by this Yuan but also by a similar one excavated at the Shang site of Hsiao-t'un.  Stone Yuans have been found as evidenced by known archaeological discoveries as far back as early Neolithic times. Jade is a stone ingrained in Chinese art, culture and history, stretching 9,000 years back into the ancient and enormous Chinese empire. Jade has always been a special stone used for fine objects especially by the Imperial Family. It is believed to be a link between both the physical and the spiritual worlds and is believed to completely encapsulates both the Yin and Yang qualities of Heaven and Earth. Measures 3 1/4" in diameter and weighs 82 grams.