WORLD COINS - JAPAN - 1 SEN - SHŌWA 20

1945 Japan 1 Sen — Shōwa 20

Tin-Zinc Wartime Type · official standard 15 mm · 1.3 g · plain edge

01 IDENTITY

Coin Identity

CountryJapan

Denomination1 Sen (0.01 Yen)

Calendar Year1945

Japanese EraShōwa 20

Date Inscription昭和二十年 (coin legend arranged right-to-left)

Coin TypeTin-Zinc 1 Sen

Issue FormatStandard circulation issue

Minting AuthorityJapan Mint

Demonetization31 December 1953 [Numista secondary catalogue]

02 PHYSICAL PROFILE

Physical Specifications

CompositionTin 50% / Zinc 50% [Japan Mint official museum record]

Official Standard Weight1.3 g

Official Standard Diameter15 mm

Japan Mint Museum Measured Example14.98 mm · 1.32 g

Catalogue Thickness1.51 mm [Numista N#9579 secondary figure]

ShapeRound

EdgePlain

OrientationMedal alignment [Numista secondary catalogue]

Japan Mint Museum records give the alloy as Sn 500 / Zn 500 and document the 1944–1945 production period. Japan Mint history gives the standard as 15 mm and 1.3 g. The museum figures shown above are measured specimens and naturally differ slightly from the nominal standard.

03 DESIGN & CONTEXT

Design & Historical Context

National Inscription & Date Side

The dated side places the national authority inscription vertically in the center with the Shōwa-era date below. The archive describes the design without reproducing third-party catalogue photography.

Denomination & Emblem Side

The opposite side places the 1 Sen denomination with chrysanthemum and plant-sprig elements. Numista is used only as a secondary descriptive cross-check for these catalogue-level design details.

Wartime Material Substitution

Japan Mint and Bank of Japan institutional materials place this coin in the wartime shift away from strategic metals. Japan Mint Museum identifies an equal tin-zinc alloy, while the Bank of Japan Currency Museum displays the 1944 tin-zinc 1 Sen among wartime substitute-material coinage.

Type Period

Japan Mint Museum records the production period of this tin-zinc 1 Sen type as 1944 through 1945. The two calendar years are therefore kept together in one type folder, with one independent archive page per year.

Artwork & Rights Note

No Numista coin photograph is reproduced. The supplied catalogue excerpt credits contributor photographs but does not establish a commercial-use licence for those images, so all such photographs are excluded from this archive package.

04 ISSUE & MINTAGE

Issue Information

Calendar Year1945

Japanese DateShōwa 20 (昭和二十年)

Secondary Reported MintageNot stated in supplied Numista table

Official Type VerificationJapan Mint confirms the tin-zinc 1 Sen production period as 1944–1945

Official Annual Mintage VerificationNot located in the consulted Japan Mint / Bank of Japan sources

Mintage Data RuleOfficial source preferred; secondary figures retained only with explicit source labeling; blank fields are not inferred

The supplied Numista N#9579 table leaves the 1945 mintage field blank. No quantity is inferred, and the archive does not transfer the 1944 total to 1945 without source support.

05 COLLECTION RECORD

Archive Information

Archive IDJP-1S-1945-SHOWA-TIN-ZINC

Coin Codejp1s45s

QR Short Codejp1s45s

QR Short URLhttps://metacoinart.com/q/jp1s45s

Canonical Path/world-coins/japan/1-sen/1944-1945-showa/1945/

Catalogue Cross-checkNumista N#9579 · Y#62 · JNDA#01-52 · Schön#39

Type BoundaryThis folder covers only the 1944–1945 tin-zinc 1 Sen type; the 1941–1943 Mount Fuji aluminum type remains in its separate archive.

06 SOURCES & REFERENCES

References

01 — PRIMARY OFFICIAL SOURCE

Japan Mint — Mint Museum Special Exhibition Exhibit List

Official Japan Mint Museum records identify the 1 Sen tin-zinc type as a 1944–1945 production issue, with composition Sn 500 / Zn 500. The museum list records measured examples at 15.11 mm / 1.33 g for 1944 and 14.98 mm / 1.32 g for 1945.

Open reference

02 — OFFICIAL HISTORICAL SOURCE

Japan Mint — 150 Years of History

Japan Mint's official history places the 1 Sen tin-zinc coin in the wartime material-substitution period and gives the Shōwa 19 standard as 15 mm and 1.3 g. The chronology records the 1944 formal establishment of the wartime 1 Sen coin type.

Open reference

03 — OFFICIAL INSTITUTIONAL CONTEXT CROSS-CHECK

Bank of Japan Currency Museum — Guide to the Exhibits

The Bank of Japan Currency Museum displays the 1944 tin-zinc 1 Sen among wartime money and explains that shortages of nickel and copper led to substitute materials such as aluminum and tin and to simplified wartime coinage.

Open reference

04 — SECONDARY NUMISMATIC CROSS-CHECK

Numista — Japan 1 Sen, Shōwa (N#9579)

Secondary cross-check for 1944–1945 dating, 15 mm / 1.3 g catalogue standard, 1.51 mm catalogue thickness, plain edge, inscriptions, catalogue identifiers and the supplied annual mintage field. No Numista photograph, valuation table, logo or catalogue prose is reproduced.

Open reference

Independent research archive. ALL THAT CURRENCY is not affiliated with, endorsed by, or sponsored by Japan Mint, Bank of Japan, or Numista. External sources are linked only as identified references.