 Since the meanings of these shapes were not mentioned prior to the eastern Zhou dynasty, by the time of the composition of the "Rites of Zhou", they were thought to represent the sky, the earth, and the four directions.By the Han dynasty, the royal family and prominent lords were buried entirely ensheathed in jade burial suits sewn in gold thread, on the idea that it would preserve the body and the souls attached to it.Jade was also thought to combat fatigue in the living.