Jade Identification--Ritual jade artifacts in ancient China

Ritual jade artifacts in ancient China consist of six worshiping items and six ceremonial items. The six worshiping items are bi-disk for heavenly deities, cong for earthly spirits,kwei, zhang, tiger shape plaque and arched plaque for the four deities in the four directions. The six ceremonial items confer to the six ranks of emperor, king, duke, marquee, viscount, baron with four different kweis and two different bi-disks. The jade knifes are not really practical arms, they are symbols for positions rather.