Shanghai one or two silver COINS, was commissioned by the Shanghai ministry of industry in 1867 by the Hong Kong mint. The main picture on the front is dragon pattern, surrounded by the Chinese character "Shanghai one or two", and on the back is the British crown and national emblem, surrounded by the English word "Shanghai one or two", the place of casting "Hong Kong", the fineness and age of the silver coin. This kind of silver coin has two kinds of awn grain and no awn grain on the front, and has the difference between the bright edge and the tooth edge.
钱币界最早对“上海壹两”进行考证而有具体结果的是中国机制铜币大师伍德华（Tracey Woodward）。他在1922年开始注意此币，至1937年发表研究心得，期间费时近十五年。其结论是“上海壹两”（Shanghai One Tael）是误写，应该是“壹上海两”（One Shanghai Tael），“上海”一词是指秤量单位，不是地名，即其本意是“漕平壹两”，并非只要在上海行用。
Tracey Woodward, a master of Chinese mechanical copper COINS, was the first one who made a textual research on "Shanghai one two" in the coin circle. He began to pay attention to the coin in 1922 and published his research in 1937, which took him nearly 15 years. The conclusion is that "Shanghai One Tael" is misspelled, it should be "One Shanghai Tael", the word "Shanghai" refers to the measuring unit, not the place name, that is, the original meaning is "cao ping One two", not only used in Shanghai.
It is worth mentioning that "Shanghai one or two" currency is the only currency issued by foreign invaders in China, which makes its value have a qualitative sublimation. It is reported that the market value of the well-preserved "Shanghai one or two" currency has reached millions, and the value is still rising. Even compared with the overseas market, the current mainland market is not inferior to anything -- collectors and investors have more abundant knowledge, broader horizons, and profound changes in concepts. They are more demanding in their pursuit of collections. Under the premise of rarity, they pay more attention to the perfect appearance, future value and historical significance of the collections!