The color and material of the sphere in the hat finial indicates an official's rank.
1 An opaque blue hat knob indicates an official of the 4th rank.
You can see why I decided to portray an official in informal uniform instead of ceremonial or formal dress. ;-) It's much less work, lol. Hats for formal occasions have a hat spike instead of a hat knob,
2 and hat quills differentiated status according to color - blue quills for 6th rank and below, peacock quills for 5th rank and above,
3 - and the number of 'eyes' in the peacock feathers.
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Formal uniform also required rank badges.
5 The ceremonial
6 necklace of 108 beads was worn by civil officials of 5th rank and higher, and military officers of 4th rank and above.
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