Could the curators please explain on what basis was the origin appraised to be 'probably Yunnan or Guangxi'? I am by no means an expert on early Southwest Chinese bronzes but I have seen my fair share around the world as well as 7-8 years in the country, 5 in Yunnan, and am still in the region writing a history that covers the earlier periods (including the time period appraised). To my mind, this object has two strong characteristics that would make it difficult to casually assign it to a Yunnanese origin within the time period specified. Firstly, it depicts a stylized dragon in pattern form that is not generally seen in that period's dominant Dian culture bronzework. Secondly, the form of the piece is abnormal; the majority of forms recovered are either bronze drums or what are believed to be cowrie containers. While this could be a such a cowrie container, it would be a fairly unique in shape compared to those I have seen. It would be worthwhile comparing this with other Guangxi, ThangLong (Red River Delta / modern Hanoi, Vietnam) and Sichuan bronzes to try to identify a similar typology. I am not sure whether mineral content analysis may be made reliably in bronze alloys, but the majority of tin mined in the region has since ancient times always come from Gejiu, further up the Red River, roughly between the 'Dian Culture' of Yunnan and the delta region around modern Hanoi/Haiphong. If such analysis is feasible, it may be worth running a test to identify the tin's origin. The Gejiu Tin mining company runs a great museum in the town (the same deposit is still under exploitation, 2000+ years later!) and can likely furnish further information on mineral properties in modern and ancient seams of the area.

There are some rare, later Nanzhao kingdom pieces in the Asian Art Gallery of San Francisco. If it were more cost effective to do so, it may be worth pooling resources to have them tested together. Musee Guimet in Paris also holds some, as does the Dali Museum in Dali, Yunnan and the Yunnan Museum in Kunming. I believe I have seen some at the National Palace Museum in Taiwan as well; I wouldn't be surprised if the British Museum had some though I have never seen any displayed.