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Wadō Kaichin: Japan's Documented 708 Court Coinage

Issued in 708 under Empress Genmei, Wadō Kaichin became the best documented landmark in Japan's early state coinage. Its four-character legend, round-square-hole form, and administrative role belong to a wider East Asian monetary tradition shaped by Tang Kaiyuan Tongbao. Archaeology now requires it to be described as a foundational documented issue, not an unqualified first Japanese coin.

和同開珎Wadō Kaichin

Wadō Kaichin: Japan's Documented 708 Court Coinage · obverse Wadō Kaichin: Japan's Documented 708 Court Coinage · reverse
Representative source specimen; not every subtype or variety.National Institutes for Cultural Heritage, Japan / ColBase · CC BY 4.0
Issue date
708-05-11
Authority
Imperial court under Empress Genmei
Form
cast round coin with central square hole
Catalog mean
24.46 mm · 3.4 g

Centralization and monetary policy

The ritsuryō court used coin issuance to express authority and support administration. It promoted holding and using coin through rank incentives and used coin in payments connected with construction of Heijōkyō. These policies show intended use; they do not prove uniform acceptance in every region.

Tang model and local issue

The Currency Museum identifies Tang Kaiyuan Tongbao as the model. Wado Kaichin adopted the circular body, square central hole, and four-character legend while serving a Japanese court program with its own inscription, authority, and historical setting.

Acceptance and value

The court assigned a high official value and promoted accumulation, salaries, and state payments. Private casting, expansion of supply, and later reductions in statutory values demonstrate that official valuation and market trust were not the same thing.

Inscription analysis

和同開珎 · Wadō Kaichin

This catalog follows the Currency Museum's Wadō Kaichin treatment because contemporary evidence does not establish that 珎 abbreviated 寳 or was read hō. The historically common Wadō Kaihō remains searchable and disclosed.

1

top character; part of the issue name

2

bottom character; often associated with the Wado era name and contemporary wording

3

right character; its regular or clerical form helps distinguish traditional catalog groups

4

left character; the source of the Kaichin/Kaiho reading discussion

Reading orientation · top → bottom → right → left

Design and production

Coins were cast rather than struck. Molten alloy entered prepared molds, connected castings were separated, and edges could be filed. Outer rims, inner rims, square holes, surfaces, and legend strength vary. Claims about a specific mother coin, mold family, mint, or production date require specimen-level evidence.

Administrative use

Documented promotion included rank incentives for accumulated coin and payments associated with capital construction. Wage and tax claims are included only where the cited source supports the specific administrative context.

Catalog dimensions

Type and variety register

These source-named groupings do not create a modern subtype census.

GroupingJapaneseMetalCalligraphyConfidenceStatus
Traditional old-style Wado grouping古和同copper alloytraditionally associated with a more regular form of 開 and rougher fabricmedium as a catalog grouping; not a stand-alone mint or exact dateresearching
Traditional new-style Wado grouping新和同copper alloytraditionally associated with a clerical-style form of 開 comparable to the Kaiyuan modelmedium as a catalog grouping; not a stand-alone mint or exact dateresearching
Silver Wado Kaichin issue和同開珎銀銭silverrequires specimen-level comparisonhigh for the existence of a documented silver issue; specialist review required for subtype claimsreview_required

Archaeology

Documented find record

One record here does not imply only one find exists; it reflects the evidence normalized in this phase.

Sūfuku-ji Temple site

Ōtsu, Shiga Prefecture · temple-site excavated specimen

Collection
Tokyo National Museum / ColBase record
Accession
E-8770
Scope
Evidence boundary

No market price, universal weight standard, mint attribution, subtype census, or authenticity verdict is inferred from a generic representative image.

Evidence

Sources and scope

These links support the claims on this page. Source authority does not imply permission to republish source images.

History of Japanese Currency Currency Museum, Bank of Japan

Fuhonsen and Mumon Ginsen context, the 708 issue of Wado Kaichin, state monetary policy, quality decline, the 958 final issue, and the return to commodity money.

Open source
Wado Kaichin Research Catalog and Measurement Guide Currency Museum, Bank of Japan

Wado Kaichin specimen classification, calligraphic distinctions, measurement method, diameter, and weight evidence.

Open source
Wado Kaichin and Ancient Coinage Exhibition Catalogue, Pages 1–5 Currency Museum, Bank of Japan

Mumon Ginsen, Fuhonsen, Wado Kaichin, Mannen Tsuho, Jingu Kaiho, documentary issue dates, circulation policy, and reading evidence.

Open source
Wado Kaichin and Ancient Coinage Exhibition Catalogue, Pages 6–10 Currency Museum, Bank of Japan

Kaiyuan Tongbao as a model, four-character naming conventions, inscription orientation, casting, and wider East Asian context.

Open source
Chemical Composition Study of the Twelve Ancient Coin Types Institute for Monetary and Economic Studies, Bank of Japan

Measured copper, tin, lead, iron, arsenic, and antimony patterns across sampled ancient coins, with specimen-level limitations.

Open source