In this study, the author analyzes in detail ya-chang excavated over the past years, arranging the artifacts into categories constituting six primary types, and comparing the cultural remains and related relics associated with each ya-chang type, while providing in-depth verification of dating. In the conclusion, the author illuminates the emergence and development of the ya-chang as a ceremonial jade, tracing its pattern of rise and decline. Furthermore, the author compares the order of development of ya-chang from various geographical regions, combined with an analysis of stratography and accompanying ceramics, concluding that the ya-chang from the Ta-wan site in Hong Kong dates from the Late Shang to the Early Western Chou (ca. 13th-mid. 10th centuries B.C.E.).