How to Identify the Chinese Song Dynasty Cash Coin

What It Is

The Song Dynasty continued China's traditional round coin with a square center hole, a format symbolizing heaven (round) and earth (square) that dates back over a thousand years earlier. The Song produced cash coins in enormous quantities across many reign periods (nianhao), and the dynasty is especially notable for issuing the same reign-title coin in multiple calligraphic scripts, a practice most famous under Emperor Huizong's elegant personal "slender gold" style.

Obverse Design

The obverse shows four Chinese characters, generally read in the order top, bottom, right, left, giving the reign title followed by a value term such as "tong bao" (circulating treasure), "yuan bao" (first treasure), or "zhong bao" (heavy treasure) — for example, "Xining Tong Bao" or "Yuanfeng Tong Bao." Song coins were cast in a wide range of script styles, including seal script, clerical script, standard script, and running or cursive script, sometimes with several script variants issued for the very same reign title.

Reverse Design

Most ordinary Song cash have a plain, blank reverse. Some issues, particularly larger-value "big cash" coins made to represent multiple standard cash units, carry a single character or numeral on the reverse indicating denomination or an abbreviated mint reference.

Size, Weight, Metal, and Edge

Standard Song cash run roughly 23-26mm in diameter with a square hole about 5-7mm across, and typically weigh around 3-4 grams, though larger denomination pieces are bigger and heavier. Both bronze and iron were used, with iron cash especially common in certain regions and periods due to periodic copper shortages. A raised rim border on both faces is typical, helping protect the inscription from wear when coins were strung together on a cord.

Mint Marks and Attribution

Many ordinary Song cash carry no explicit mint mark at all. Where regional or mint attribution is possible, it generally relies on subtle differences in character style and any reverse marks found on specific later Southern Song issues, cross-referenced against specialist catalogs rather than an obvious inscribed mint name.

Telling It Apart from Similar Coins

The reign-title text is the fastest way to separate Song cash from other dynasties' cash coins: Tang coins read "Kaiyuan Tong Bao" regardless of when during that dynasty they were struck, while Song and later Ming and Qing coins each use their own distinct reign-title characters. Modern souvenir "feng shui" cash coins sold widely today often carry incorrect or fantasy inscriptions that do not match any genuine historical reign title, which is a useful check against a real Song catalog listing.

Judging Condition at a Glance

Because Song cash were cast in molds rather than struck, look for crisp, well-formed raised characters, a cleanly centered square hole, and minimal casting flash or burrs around the edge. Even, natural-looking patina built up over centuries adds to a coin's presentability.

Authenticity Red Flags

Genuine cash coins display natural, uneven oxidation in shades of green, brown, or black built up gradually over centuries, along with correct, recognizable calligraphy matching documented reign-title coins. Modern fakes often show an unnaturally uniform, sandy-cast surface texture, incorrect or garbled stroke forms, the wrong metal color or weight, or a chemically applied "aged" look that appears too even and artificial.