Liang (currency)
Liang, or leung in Cantonese, also called "Chinese ounce" or "tael", was a traditional Chinese unit of currency measurement.
File:後藤分銅1.jpg|thumb|right|300px|Japanese Edo era liang weights for balance scales, made of bronze. In descending size, 30, 20, 10, 5, 4, 3, and 2 liang weights.
In China, there were many different weighting standards of liang currency depending on the region or type of trade. In general, the silver liang weighed around. The most common government measurement was the Kuping liang, weighing. A common commercial weight, the Caoping liang weighed of marginally less pure silver.
Imperial China
Traditional Chinese silver sycees and other currencies of fine metals were not denominated or made by a central mint and their value was determined by their weight in liangs. They were made by individual silversmiths for local exchange, and as such the shape and amount of extra detail on each ingot were highly variable; square and oval shapes were common but "boat", flower, tortoise and others are known. The liang was still used in Qing dynasty coinage as the basis of the silver currency and sycee remained in use until the end of the dynasty in 1911. Common weights were 50, 10, 5 and one liang. Before the year 1840 the government of the Qing dynasty had set the official exchange rate between silver sycees and copper-alloy cash coins was set at 1,000 wén for 1 liang of silver before 1820, but after the year 1840 this official exchange rate was double to 2,000 wén to 1 liang.During the reign of the Xianfeng Emperor, the government of the Qing dynasty was forced to re-introduce paper money, among the paper money it produced were the Hubu Guanpiao silver notes that were denominated in liangs.
The forced opening of China during the Qing dynasty created a number of treaty ports alongside the China's main waterways and its coastal areas, these treaty ports would fundamentally change both the monetary system of China as well as its banking system, these changes were introduced by the establishment of European and American merchant houses and later banks that would engage in the Chinese money exchange and trade finance.
Between the years 1840 and 1900, 1 market liang was worth 1.38 Spanish dollars.
Various Western banking companies, the largest of which were the HSBC, and later Japanese banking companies started to begin to accept deposits. They would issue banknotes which were convertible into silver; these banknotes were popularized among the Chinese public that resided in the treaty ports.
An important development during this era was the establishment of the Imperial Maritime Customs Service. This agency was placed in charge of collecting transit taxes for traded goods that were shipped both in and out of the Chinese Empire, these rules and regulations were all stipulated in various trade treaties that were imposed on the Qing by the Western colonial powers. Because these changes were implemented during the height of the Taiping Rebellion, the Western powers had managed to take over the complete administration of the Qing's maritime customs from the imperial Chinese governmental bureaucracy.
The Imperial Maritime Customs Service developed the Haikwan liang, this new form of measurement was an abstract unit of silver liang that would become the nationwide standard unit of account in silver for any form of Customs tax. The Haikwan liang was preferred over the Kuping liang by many merchants across China, this was because the units of the Kuping tliang varied often to the advantage of imperial tax collectors, this form of corruption was an extra source of income for government bureaucrats at the expense of traders. The Haikwan liang unit was completely uniform, it was very carefully defined, and its creation had been negotiated among the various colonial powers and the government of the Qing dynasty. The Haikwan liang was on average 5% to 10% larger than the various local liang units that had existed in China, this was done as it deliberately excluded any form of extra surcharges which were embedded in the other units of the silver liang that existed as a form of intermediary income for local government tax collection, these surcharges were added to local liangs as a form of corruption and these taxes never reached the imperial government under the traditional fiscal regime.
Near the end of the Qing dynasty, one was about 50 liangs.