Magatama

Magatama ( or ), are curved beads which first appeared in Japan during the Jōmon periodThey are often found inhumed in mounded tumulus graves as offerings to deities (see grave goods). They continued to be popular with the ruling elites throughout the Kofun Period of Japan, and are often romanticised as indicative of the Yamato Dynasty of Japan. Some consider them to be an Imperial symbol, although in fact ownership was widespread throughout all the chieftainships of Kofun Period Japan. It is believed that magatama were popularly worn as jewels for decoration, in addition to their religious meanings. In this latter regard they were later largely replaced by Buddhist prayer beads in the Nara period.
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[Japanese] The sacred stones of Shinto. They are pear-shaped pieces of crystal (agate, jasper, etc.) and are used for religious purposes.