This is an old Chinese cash coin from the Qing (Ch'ing) Dynasty (1644-1911), Emperor Ch'ien Lung (Gao Zong), (1736-1795). It has a broad rim and is from the Hangzhou, Zhejiang mint. The Chinese characters on the front read 'Qian Long Tong Bao'. The Manchu characters on the back vary by mint. On our coin they read 'Boo Je', corresponding to the Hangzhou in the province of Zhejiang - a rare mint. The most common mints are 'Boo Yuwan', the 'Board of Public Works' mint in Beijing, and 'Boo Chiowan' or the 'Board of Public Revenue' mint, also in Beijing. There are many other smaller provincial mints, the coins from which are generally more valuable. It is beyond the scope of CoinQuest to list and evaluate all these varieties. A good coin catalog will tell you much more!
The coin in our primary picture is from Noble Numismatics in Australia. This particular coin is in great shape and sold for 180 AUD (about $160 US dollars) in a 2009 auction.
Some coins of rare mints in superb condition can reach as high as $1000, but most coins are heavily worn and carry values between $2 and $10.
In our secondary picture we have included the qian long tong bao side of Melville's coin. He sent us this picture. You can see it is in rough shape compared to the Noble specimen. Melville's coin would probably sell for about $10 to $20 US dollars.