Japanese silver hallmarks
Japanese silver is usually marked with letters and a number, such as SV925, and sometimes with kanji. This guide explains what each one claims, how the Japanese rules differ from other countries, and what the official Japan Mint mark is. If you are new to hallmarks, start with how to read hallmarks on vintage silver.
Letters and numbers
Most Japanese silver jewelry is marked with a short code for silver followed by the fineness, the share of silver in every thousand parts.
| Mark | What it claims |
|---|---|
| SV925 | 92.5% silver. SV is the most common Japanese short form for silver. |
| SV950 | 95% silver. In our shop we see it most often on Japanese tableware, such as cups and spoons. |
| Ag925 | The same claim as SV925, using the chemical symbol for silver. |
| SILVER925 | The same claim, written out in English. |
| STERLING | 92.5% silver, as everywhere else. |
| SV, SILVER | No number. Under the Japanese industry guideline, these may only be used on silver of at least 925. |
That last row is the main difference from many other countries. Elsewhere, a plain SILVER mark says nothing about the amount. In Japan, the jewelry industry's own guideline treats it as a claim of at least 925. The guideline applies to pieces sold under it, so an imported or much older piece may not follow it.
Kanji marks
- 純銀 (jungin) means pure silver. The guideline reserves it for silver of 999 and above.
- 銀 (gin) means silver. Used alone, without a number, the guideline treats it as at least 925.
- 銀製 (ginsei) means made of silver. Used alone, the guideline treats it as at least 800.
The guideline also says a piece below 800 should not be sold as silver jewelry at all, and it does not allow a fineness of 1000, since no silver is perfectly pure.
The Japan Mint mark
The Japan Mint, part of the national government, tests precious metal goods and strikes its own certification mark on the pieces that pass. The mark includes the Japanese national flag together with the fineness. The Mint has offered this service since 1929.
The Mint mark is voluntary. Most Japanese silver jewelry does not carry it, so a missing Mint mark is not a warning sign. When it is present, it is the strongest claim a Japanese piece can make, because a public body tested the metal rather than the maker.
Marks that mean plating, not solid metal
- SP stands for silver plated: a thin layer of silver over another metal.
- SILVER F stands for silver filled: a thicker layer of silver bonded to a base metal. It wears longer than plating but is still not solid silver.
- K18GP means plated with 18 karat gold. The K18 describes only the thin gold layer, not the metal underneath. You see this style often on Japanese pieces.
- K18GF means gold filled with 18 karat gold: a thicker gold layer, but still not solid gold.
These letters are easy to miss next to the word SILVER or a karat number. Read the whole stamp, not just the first word. For the full list of plating marks, including EPNS, HGE and vermeil, see the plating section of our hallmarks guide.
A quick way to read a Japanese piece
- A number after SV, Ag or SILVER is the fineness.
- SV or SILVER with no number claims at least 925 on a piece sold under the Japanese guideline.
- 純銀 claims 999 or higher.
- A flag mark with a number is the Japan Mint certification.
- SP, SILVER F, GP or GF means a thin layer of metal, not solid metal.
As with any stamp, these record a claim. Copper pieces coated in silver can carry convincing marks, so buy from sellers who accept returns.
Sources
- Japan Jewellery Association, guide to precious metal marking (in Japanese). Source for the SV, SILVER, 純銀, 銀 and 銀製 rules.
- Silver hallmarks (Wikipedia). Source for the Japan Mint hallmarking since 1929 and the flag in its mark.
- Nanboya, guide to silver marks (in Japanese). Source for SP and SILVER F as plating marks and the voluntary Mint mark.
- Nanboya, real gold and gold plating (in Japanese). Source for K18GP and K18GF.