Archaic Chinese characters Yi Hua / Blank. 22mm, 1.7 grams. Hartill #6.23; Gratzer/Fishman "Early Round Coins of China" #9.1 (rated Very Rare).

The Qi are known for their beautiful large knife-coins. The only round coins attributed to the State of Qi come from a single series of three different denominations – 1-, 4- and 6-hua coins cast by King Xiang in Shandong (perhaps in Yidu (modern Qingzhou)). The word Hua 化 is the local unit of measure used in north-eastern China. Presumably, hua weighed somewhere around 1.5-2 grams, though the exact weight of a hua is unknown.

The State of Qi was one of the most powerful and enduring states during ancient China's Zhou dynasty, particularly prominent in the Spring and Autumn (770–476 BCE) and Warring States (475–221 BCE) periods. Located in what is now Shandong province, Qi was originally granted to the Jiang clan by King Wu of Zhou and rose to prominence through its strong economy, skilled bureaucracy, and early political reforms. One of its most famous rulers, Duke Huan of Qi, became the first of the recognized Hegemons (ba) during the Spring and Autumn period, asserting leadership over other states under the nominal authority of the Zhou king.

Qi is notable for early economic innovations, including the issuance of knife-shaped coinage, such as the three-character knives, and for fostering philosophy and learning, particularly at Jixia Academy, a famed intellectual center that attracted thinkers from across China. Despite its wealth and power, Qi was ultimately conquered by the State of Qin in 221 BCE, just before the unification of China under the Qin dynasty. Its legacy remains significant in Chinese history for its cultural, political, and economic contributions.