Henan Province is situated on the lower basin of the Huanghe River. There are a number of important historical sites dating from the Paleolithic era to the time of Ming-Qing Dynasty, among which are sites related to ceramic production. In Gongyi City, situated between the provincial capital of Zhengzhou and the city of Louyang in Henan Province, remains of kilns can be found within an area ranging over approximately 160,000 square meters. Remains of kilns for the manufacture of white and celadon ceramics, as well as Tang Sancai (three-colored glazed Tang ceramics), were known to exist in the villages of Da Huangye, Xiao Huangye and Baihe. Tang Sancai is known to have been carried not only throughout East Asia, but throughout the world, so the kilns in this area have attracted worldwide attention. The remains of the kiln in Gongyi, however, have been the subject of small-scale excavation and surveying only, thus a full-scale study is needed to shed light on the production of Tang Sancai as a whole. The kiln remains in this region are of great significance in explaining the origins of Tang Sancai discovered in Japan, as well as the evolution of Nara Sancai (three-colored glazed Nara ceramic). Therefore, the Nara National Research Institute for Cultural Properties (hereafter Nabunken) and the Archaeological Institute of Henan Province concluded an agreement in 2000 to undertake ongoing research on the remains of Gongyi kiln and the artifacts found at the site. Since then, researchers from both institutions have visited each other, and research on Sancai and related materials in China and Japan continues.

Between the years 2002 and 2004, we carried out an excavation of the Huangye kiln remains in villages of Da Huangye,Xiao Huangye , where we found a number of valuable artifacts and structural remains, including Sancai ceramics, pottery, and related tools, as well as a kiln and a workshop. The Sancai ceramic pillow discovered at this site showed patterns and production techniques identical to those of a ceramic pillow found at Daianji Temple in Nara, demonstrating that some of the Tang Sancai found in Japan was produced in the Hangye kiln. In addition to Tang Sancai, we discovered Tang Dynasty celadon and white floral porcelain, identical to that which had been found earlier at Yangzhou castle, and were able to specify the origin of this style of ceramic for the first time.
Subsequently, from 2005 to 2008, we carried out an excavation of the Baihe kiln in the village of Baihe. The first Tang Sancai horse to be found in Gongyi kiln was discovered in this excavation, increasing the possibility that this kiln was the site of production for the ceramic figures found in the tombs in Luoyang. Besides Tang Sancai, we discovered white and celadon ceramics, thought to be from Northern Wei Dynasty , which was a significant achievement in terms of identifying the origin of early Chinese white ceramics. White ceramics thought to have been produced in Baihe was discovered in Luoyang castle, the capital of Northern Wei*, which further highlighted the connection between the two.
As a result of this research, we concluded that the majority of the Tang Sancai found in Japan most likely originated at the Gongyi kiln, which will bring us further insights regarding the development of Nara Sancai.

Along with the excavation, we have been carrying out archival research in order to evaluate the archaeological findings from the Huangye and Baihe kilns. We investigated materials held by various institutions in Japan and China, including the Archaeological Institute of Henan Province, and the Gongyi Museum. Researchers from Nabunken visited China, and, together with their counterparts at the Archaeological Institute of Henan Province, studied Tang Sancai and related materials in various institutions. Furthermore, each year academics from China were invited to conduct research on materials at Nabunken and other institutions in Japan. In addition, Nabunken organized a series of lectures by visiting Chinese researchers on the latest developments in archaeological research in Henan.
　Detailed results of this research can be found in two illustrated publications: Gongyi Huangye Tang Sancai (2003); and New Archaeological Discoveries from the Huangye Tang Sancai Kiln (2006), and in An archaeological research leading report on the Henan Gongyi Huangye kiln (2010), which contains an excavation report and scientific findings. In addition, a special exhibition entitled Legendary Tang Masterpieces : New Archaeological discoveries of Huangye Tang Sancai was held at Asuka Historical Museum in the fall of 2008. Nabunken researchers also participated in conferences held in China, where they reported on the latest findings. We intend to continue our joint research, and have some forthcoming publications, an illustrated publication on the Baihe kiln, and an excavation report on the remains of the Huangye and Baihe kilns.