Chinese Copper Coins (Tong Qian) specifically refer to the round coins with a square hole, which were the standard currency from the Qin Dynasty to the early 20th century. Their design—a circle enclosing a square—reflects the ancient worldview of "round heaven, square earth." The circle symbolizes limitless abundance, while the square represents stability and order, together meaning "wealth that gathers and holds."

In tradition, these coins are considered powerful symbols for attracting prosperity, protecting against negative energy, and blessing homes and wearers.

The "Five Emperor Coins"—minted under five Qing emperors—are among the most renowned feng shui talismans. They are believed to harmonize the Five Elements' energy and attract good fortune. Handled by countless people, the coins accumulate strong Yang Qi, which can neutralize stagnant or negative influences. Coins from prosperous reigns symbolize accumulated wealth and, when used in alignment with wealth energy layouts, are thought to enhance financial flow. They also represent heritage, integrity, and the stable, rightful accumulation of resources.