The two bronze shell coins are similar to sea shells in shape. They were modeled on the sea shells with the back polished, commonly known as “ghost face coins” or “ant nose coins”. They were a type of bronze coins unique to and circulated in the State of Chu as the main coinage.
There were bronze shell coins in the Shang and Western Zhou dynasties, but they were all without inscriptions. The bronze shell coins without inscriptions were continuously minted in the middle and lower reaches of the Yellow River during the Spring and Autumn Period and the Warring States Period. Thousands of bronze shell coins without inscriptions were unearthed in Hui County in Henan Province, Houma County in Shanxi Province, and Linzi District of Zibo City in Shandong Province, including dozens of gold-covered bronze shell coins. The bronze shell coins with inscriptions were unique to the State of Chu. So far, nearly 10 types of such coins have been discovered, including those with the inscriptions of “Tao”, “Jin”, “Xing” and “Jun”. The most are those shown on the left.