Japan
Japan's hallmark is optional — a guarantee struck by the national Mint, marked with a rising-sun flag and the fineness, on a strong market for platinum.
In the atlas: Ginza Jewelry District
Voluntary marking
The Japan Mint (Zōheikyoku) has assayed precious-metal wares since 1929; the mark was last revised in 2012. It has never been compulsory.
Voluntary certification by the Japan Mint, on request.
What you'll see struck
Japan Mint hallmark
Mint purity guarantee
A hinomaru (rising-sun) flag device certifies the Mint-assayed fineness, struck beside the purity number.
Fineness lozenge
Certified purity
The fineness set in a diamond/lozenge outline, e.g. <999>, <750>; platinum adds a boxed Pt.
Fineness
- Platinum
- 850 · 900 · 950 · 999 (strong market)
- Gold
- 375 · 416 · 585 · 750 · 916 · 999
- Silver
- 800 · 900 · 925 · 950 · 999
Hallmark Calculator
See how Japan's standards line up with any other country — translate a grade, or compare side by side.
A reference guide, not an authentication service. Marks vary by date and metal; consult the relevant assay office or standards body for definitive identification.