They are mostly ox scapula and turtle shells or plastrons which when heated would cracked. Their use as a method of divination in China seems to date back to the middle of the Shang Dynasty, probably in the reign of Pangeng, around 1350 BC when the Shang capital was moved to Yin. The site at Anyang is believed to be the site of this ancient capital.

They were also called dragon bones on account of their discovered use when they were found sold in Chinese medicinal centres either whole or crushed for the healing of various ailments.

See also: Oracle Script