1955–1989 Japan 1 Yen — Shōwa Aluminum Type
Shōwa 30–64 · Young Tree · 35 calendar years (1968 non-issue)
Select a Year
1968 (Shōwa 43): the official Japan Mint table reports 0 year-dated aluminum 1 Yen coins. That year card opens a non-issue explanation, not an issued coin record. The 1987 and 1988 year records link to separate Proof variety pages.
The Aluminum 1 Yen Coin
Japan Mint documents the modern aluminum 1 Yen coin as first issued in 1955 after a public coin-design competition. The Bank of Japan specifies 100% aluminum, 20 mm in diameter, 1.0 g in weight and a smooth edge. Only the date inscription changes among the year-dated coins in this Shōwa series.
Official Sources & Catalogue Cross-check
Japan Mint — Coins Manufactured by Year and Denomination
Japan Mint primary manufacturing count for Shōwa 30 (1955); the table gives the year-dated 1 Yen aluminum amount, not a separate breakdown by collector finish.
Japan Mint — A History of the 1 Yen Coin
Japan Mint historical account: the 1 Yen aluminum coin entered circulation in 1955 after a public design competition and uses a 20 mm, 1 g format.
Bank of Japan — Notes and Coins Currently Issued
Bank of Japan identifies the current aluminum 1 Yen coin as 100% aluminum, 20.0 mm in diameter, 1.0 g, smooth edged and bearing the young-tree design.
Numista — Japan 1 Yen, Shōwa (N#1590)
Catalogue listing for Shōwa years, inscriptions, 1.2 mm reported thickness, and the 1987/1988 Proof variety entries. No Numista photographs, valuations, logos or catalogue prose are copied.
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 provided as identified references only.
Review flags: 1971 and 1976 values in Numista differ from Japan Mint official manufacturing totals; both are shown with attribution on the respective year pages. 1987 and 1988 Proof variety quantities are secondary and are not verified as distinct official counts.