Huang was used to honor gods in the north. It looks like a half of a Bi and a theory is that the shape is an imitation of rainbow.
40 Huang were unearthed from the Zeng Hou Yi mausoleum. They were placed in pair. This pair of Huang is connected by three gold wire and the jade is very fine, with only a little brown color on one end. This is the only artifact that combines gold and jade in Pre-Qin Period.