Mineral origin of tremolite jade artifacts from the Guojiamiao Cemetery, Eastern Zhou Dynasty, Hubei, China: based on petrology, spectroscopy, and geochemistry

The origin of raw materials is a key area of study in jade archaeology, with significant implications for understanding the interactions and exchanges between ancient cultures. The Guojiamiao Cemetery, located in Zaoyang City, Hubei Province, China, has been the subject of two protective excavations, one in 2004 and another in 2014. These excavations revealed a large aristocratic cemetery from the Zeng State, dating from the late Western Zhou Dynasty to the early Spring and Autumn periods. The jade artifacts found at the site are diverse in type and exquisite in craftsmanship, serving as important burial items. This study applied gemological, spectroscopic, and geochemical methods to analyze 30 jade artifacts in detail. We examined the types of minerals, shape characteristics, and chemical composition of the materials. In particular, we focused on determining the origin of the tremolite jade artifacts found at the cemetery. Using a classification method based on combinations of trace and rare earth elements associated with different regions, we were able to identify the sources of the jade. Our findings suggest that the raw materials for the Guojiamiao Cemetery jade artifacts unearthed were transported over long distances, from northwestern China to the middle reaches of the Yangtze River. This research is important for understanding the jade use system of the Zeng State from the early Western Zhou to the mid-Warring States periods. It also provides insights into the sources of jade materials in different historical periods of the Zeng State and its connections with the Chu State. Ultimately, this study contributes to a broader understanding of the evolution of civilization in the middle Yangtze River region.