说明：“中圆”为袁大头银圆中最为罕见的面额。1914年2月《国币条例》规定，一圆主币成色仍为90%，五角以下辅币均改为70%。后来财政部以“因时制宜，与原条例略有出入”为由，改成色为89%。同时为实现金本位币制作准备，将五角辅币名称定为“中圆”。1916年7月，财政部应造币总厂所请，先在天津发行了含银70%的中圆、二角、一角3种新银辅币，并力推十进制结算法。虽然北洋政府三令五申努力推广新银辅币，但十进制改革效果不彰。到1923年时风潮迭起，十进制几近崩溃：市场仍按含银量折算，新辅币与旧辅币已无分别，天津造币厂还被币制局训令停产。档案中可査到的袁像中圆产量，尚不及同时期一圆主币产量的千分之五。另外一个重要因素是习用中圆辅币的地方有限，各地最乐用的辅币还是二角及一角。袁像中圆主要在北方各省流通，在十进制改革失败后，使用上无任何便利之处。中圆在上海称“袁像对开”，市价要十三角一二分。即使在产地南京，通用的仍以广东、江南、湖北等地造的旧式毫子居多。即使是邻近总厂的北京，辅币也是以小洋一角最为通行。

Author - 31 mm in diameter; 13.5g in weight, for the time being, there are countless quantities: 1.
Explanation: "Zhongyuan" is the most rare face of Yuan Datou Yinyuan. In February 1914, the National Currency Regulations stipulated that 90% of a dollar's principal coin was still coined and 70% of the minor coins below 50 cents were coined. Later, the Ministry of Finance changed its color to 89% on the grounds of "adjusting measures according to the time and slightly different from the original regulations". Meanwhile, in order to prepare for the production of gold standard currency, the name of the Pentagon coin is designated as "the middle circle". In July 1916, at the request of the Mint General Factory, the Ministry of Finance first issued three new silver coins in Tianjin, including 70% silver in the yuan, dihedral and dihedral, and pushed forward the decimal settlement method. Although the Beiyang government has made great efforts to promote the new silver coin, the decimal system reform has not been effective. By 1923, the trend was repeated, and the decimal system was almost collapsed: the market was still converted into silver, the new and old coins were no longer different, and the Tianjin Mint was ordered to stop production by the Monetary Bureau. The output of Yuan's image in the archives is less than five thousandths of the output of one yuan in the same period. Another important factor is the limited use of the Chinese yuan coins, and the most popular coins are the dime and the dime. Yuan Xiangyuan circulated mainly in the northern provinces. After the failure of the decimal system reform, there was no convenience in its use. Zhongyuan is called "Yuan Xiangbiao" in Shanghai, and its market price is 13.12 cents. Even in Nanjing, where it originated, most of the old-fashioned millions are made in Guangdong, Jiangnan and Hubei provinces. Even in Beijing, which is adjacent to the main factory, the dime of Xiaoyang is the most popular coin.