Cash (Chinese coin) in the context of "String of cash coins (currency unit)"

Cast coinage refers to coins made by pouring melted metal into a mold, i.e. casting. It has been used for regular coins, particularly in East Asia, but also other areas on a smaller scale (e.g. the ancient Mediterranean world). The method differs from the current mode of coin production, which is done by striking coin blanks that have been cut out of metal sheets. The method has also been used by forgers.

Traditional Far Eastern cast coins—so-called 'cash coins'—are the most famous example of cast coinage, and were issued from the 4th century BC until c. 1912, predominantly in bronze, brass or iron. Traditional Far Eastern coins were generally cast base metal coins, although silver and gold bars were also manufactured, e.g. Chinese sycee, Japanese obans and kobans, and Vietnamese lang and tien.

Celestial Empire (Chinese: 天朝; pinyin: Tiāncháo; lit. 'heavenly dynasty') is an archaic name used to refer to China or the Chinese Empire, from a literary and poetic translation of the Chinese term, one of many names for China. The name was used in reference to the status of the Emperor of China as the Son of Heaven in the Sinosphere.

Accordingly, in the 19th century, the name "Celestial" was used to refer to Chinese people. Both terms were widely used in the English-language popular mass media of the day, but fell into disuse later on. Its usage has become popular again in the present day (2015), particularly among Chinese Internet users. It is used to refer to the current Communist regime, to imply either disapproval for its political suppression and arrogance or national pride in the country's emergence as a superpower in the 21st century, depending on the context.

Spade money (traditional Chinese: 布幣; simplified Chinese: 布币; pinyin: bù bì) was an early form of coin and commodity money used during the Zhou dynasty of China (1045 to 256 BCE). Spade money was shaped like a spade or weeding tool, but the thin blade and small sizes of spade money indicate that it had no utilitarian function. The earlier versions of spade coins tended to have a fragile, hollow socket, reminiscent of a metal shovel. Later versions of spade money had this socket transformed into a thin, flat piece, and over time, inscriptions were added to the spade coins to mark their denominations. Several versions of spade money circulated across the Chinese Central Plains during the Zhou dynasty period until they were abolished by the Qin dynasty in 221 BC in favour of the Ban Liang cash coins.

Under the Xin dynasty created by Wang Mang spade money was reintroduced; there were 12 different types of spade money in the Xin dynasty, ranging in values from 100 to 1000 qián.

The history of Chinese currency spans more than 3000 years from ancient China to imperial China and modern China. Currency of some type has been used in China since the Neolithic age which can be traced back to between 3000 and 4500 years ago. The history of China's monetary system traces back to the Shang dynasty (c. 1766–1154 BCE), where cowrie shells served as early currency. Cowry shells are believed to have been the earliest form of currency used in Central China, and were used during the Neolithic period. By the Warring States period, diverse metal currencies like knife and spade coins emerged. These early currencies, starting as a commodity exchange to cowrie shells, copper coins, paper money and modern Chinese currencies and digital currencies shows how centralized power developed the most influential monetary system in the world.

The Ryukyuan mon (琉球文, Ryūkyū mon; Okinawan: Ruuchuu mun) was the currency used in the Ryukyu Islands. The Ryukyuan monetary system was based on that of China, like those of many nations in the Sinosphere, with the mun (文) serving as the basic unit, just as with the Japanese mon, Vietnamese văn, and Korean mun. Like Japan had also done for centuries, the Ryukyuans often made use of the already-existing Chinese cash coins when physical currency was needed.

In the 14th and 15th centuries, the Kingdoms of Chūzan and Ryukyu produced their own coinage, but eventually transitioned back to Japanese mon and Chinese wén. Regardless of their origin, mon coins remained the de facto currency in the Ryukyu Kingdom throughout history up until 1879, when the kingdom was fully annexed by the Empire of Japan and the currency was officially replaced by the Japanese yen. Even after the introduction of the yen, however, mon coins continued to circulate within Okinawa Prefecture well into the 1880s, as the Ryukyuans were initially unwilling to use Japanese yen coins.

The Vietnamese cash (chữ Hán: 文錢 văn tiền; chữ Nôm: 銅錢 đồng tiền; French: sapèque), also called the sapek or sapèque, is a cast round coin with a square hole that was an official currency of Vietnam from the Đinh dynasty in 970 until the Nguyễn dynasty in 1945, and remained in circulation in North Vietnam until 1948. The same type of currency circulated in China, Japan, Korea, and Ryūkyū for centuries. Though the majority of Vietnamese cash coins throughout history were copper coins, lead, iron (from 1528) and zinc (from 1740) coins also circulated alongside them often at fluctuating rates (with 1 copper cash being worth 10 zinc cash in 1882). Coins made from metals of lower intrinsic value were introduced because of various superstitions involving Vietnamese people burying cash coins, as the problem of people burying cash coins became too much for the government. Almost all coins issued by government mints tended to be buried mere months after they had entered circulation. The Vietnamese government began issuing coins made from an alloy of zinc, lead, and tin. As these cash coins tended to be very fragile, they would decompose faster if buried, which caused the Vietnamese people to stop burying their coins.

The inscriptions of Vietnamese cash coins can be written in either the Viết chéo (曰湥 / 曰袑, top-bottom-right-left) style or the Viết thuận (曰順, clockwise, top-right-bottom-left) style.