As jade was believed to incorporate the essences of heaven and earth, it was used as a medium of communication be tween shamans and the gods, a specific type being allocated to each deity.
One of the rituals an emperor would perform upon assuming power was that of "casting dragon slips." This involved the new ruler's climbing to the summit of a well-known mountain and throwing down engraved slips of jade, notifying the mountain gods of his succession. When the emperor fell ill. his shaman would go to the mountain and cast jade slips engraved with prayers for the monarch's recovery.
This ritual has been confirmed in recent years by the discovery of two such jade slips at the foot of Huashan Mountain dating back to the Warring States Period(475-221 B.C.), carved on either side with prayers for the recovery of the ailing King of Qin.
