We've learned about four of the ancient Chinese Six Ritual Jades:
Cong - earth, Bi - sky/heaven, Huang - North, and Hu - West.
Another of the Six Ritual Jades was the Gui.
This was a kind of blade, and it was used to mean "East".
(from: wikipedia - commons: jade gui in the western han dynasty)
Kid Facts - Blast from the past: Judith and Holofernes - Donatello