Ts'ung Tube
T'ao-ssu Culture Style (ca. 2400-2000 B.C.)
Height: 2.9 cm, width: 7.1 cm,
diameter of hole: 6.2 cm, thickness: 0.63 cm

  This ts'ung tube, carved from grayish-green jade with streaks of brown on one side, is round on the inside and square outside. The walls of the object are quite thin and it has a relatively large hole. With a short neck, the inside of the mouth and rim are round. The inside wall of the hole has been polished to a smooth surface, and the middle of each of the four sides protrudes slightly with a wide groove carved down the center.

  A later gilt bronze incense burner was made to fit inside and give this ts'ung tube a new function.

Traditional studies on ts'ung tubes in "Illustrated Study of Ancient Jades"

  ...mention that what were once considered small ts'ung tubes were actually decorative wheel fixtures on the sedan chairs of rulers. Larger ones were the actual ts'ung tubes and served as jade ritual objects for venerating the earth deity.

Ts'ung Tube  
Ch'i-chia Culture Style (ca. 2200-1800 B.C.)
Height: 13.4 cm, max. width: 7 cm,
diameter of hole: 5.1 cm, thickness: 0.93 cm

  Carved from grayish-green jade with streaks of brown and white, this ts'ung tube is lustrous and has "sugar-brown and white" coloration. The width of both ends differs. The mouth was cut at an angle and is round inside but not outside. The neck is slightly elongated, and the four sides are flat. The wall of the hole inside is straight and lustrous.

  Jades referred to as "Ch'i-chia culture style" indicates that they are similar in many ways to archaeologically recovered jades from the Ch'i-chia culture, but they cannot be positively identified as such.

Pi Disk  
Ch'i-chia Culture (ca. 2200-1800 B.C.)
Max. diameter: 28.4 cm, diameter of hole: 5.35 cm, thickness: 1.9 cm

  Carved from light green jade, the surface of this disk has weathered to a reddish hue. Uneven in thickness, one side protrudes slightly yet is still level. The other side is damaged. The hole was drilled from one side and is relatively small in diameter.

  The level side is engraved on the left and right with poetry of the Ch¨ien-lung Emperor (r. 1736-1795), whose imperial seals appear engraved at the top and bottom. Only an imperial seal is engraved on the back at the top and bottom. A square sandalwood screen stand with a plug in the middle was specially designed for the disk.

Traditional studies on pi disks in "Illustrated Study of Ancient Jades"
  ...mention that the round shape of the pi disk was a symbol for the heavens and that green pi disks were used to venerate heaven.