What does 900 mean on jewelry?
Short answer
900: 900 parts per thousand silver or 900 parts per thousand gold or 900 parts per thousand platinum.
The figure alone does not name the metal: the metal’s colour and the accompanying marks decide.
The stamp in detail
| Item | What the tables say |
|---|---|
| Stamp | 900 |
| Class | Fineness (purity) mark |
| Silver fineness | 900 parts per thousand (90 % silver) |
| Legal standard (silver 900) | United States (coin silver) |
| Source check | Checked against the sources listed below |
| Gold fineness | 900 parts per thousand (90 % gold) |
| Legal standard (gold 900) | No statute recorded in our tables; common in trade or by arithmetic |
| Note | Coin gold (21.6 karat). |
| Source check | Not checked against a statute: arithmetic or trade usage |
| Platinum fineness | 900 parts per thousand (90 % platinum) |
| Legal standard (platinum 900) | United Kingdom, Vienna Convention states, France, United States |
| Source check | Checked against the sources listed below |
What is 900 worth by weight?
Every gram of a piece stamped 900 holds 0.9 g of fine silver, if the stamp is accurate. Multiply that by the spot price of silver to get the melt value. It is the floor, what the metal is worth if melted, not what a buyer will pay and not an appraisal.
Example, clearly not live: 10 g at the example price of $51.87 per troy ounce (snapshot of 2026-11-10) is $15.01. The working: 10 g → 900 / 1000 → 10 g × 0.9 → 51.871 USD/ozt ÷ 31.1034768 g/ozt → 9 g × 1.6677 USD/g.
This number is used for more than one metal; the calculator below lets you pick.
Melt value calculator for 900
Enter a weight and a stamp to see the sum.
Today's spot price: LBMA precious metal prices, Kitco live gold or your own dealer's quote. This page never contacts a price service.
What 900 can be mistaken for
Pieces that look like gold and are not:
- plated and gold filled
- pinchbeck and gilt brass
- silver gilt (vermeil)
What a stamp cannot settle: The metal. Colour is not a fineness, and a mark can be forged.
What settles it:
- Magnet: if it sticks, it is not solid gold (not sticking proves nothing).
- Jeweller: touchstone and acids, or X-ray fluorescence, in two minutes.
Cautions
- The figure alone does not name the metal: the metal’s colour and the accompanying marks decide.
- A mark is a statement, not proof: it can be forged or struck on a plated piece. An assay confirms it (touchstone and acids, or X-ray fluorescence).
Related stamps
Other ways the same fineness is stamped: COIN, IRIDPLAT.
Frequently asked
What does 900 mean on jewelry?
900: 900 parts per thousand silver or 900 parts per thousand gold or 900 parts per thousand platinum.
Does 900 mean the piece is solid silver?
It means the piece is stamped as silver, gold, platinum, 900 parts per thousand. The figure alone does not name the metal: the metal’s colour and the accompanying marks decide.
How much fine silver is in a piece stamped 900?
0.9 g of fine silver per gram of metal, if the stamp is accurate. Melt value is that weight times the spot price. It is not an appraisal.
Sources
- Hallmarking Act 1973, Schedule 2 (revised text)
- Vienna Convention on precious metals, Technical Decisions Rev. 13 (in force 1 Oct 2026)
- 15 U.S.C. § 296 (silver: sterling and coin)
- FTC Jewelry Guides, 16 CFR 23.5 (silver)
- Arithmetic: karats / 24 × 1000 (no external source)
- Douane française, table of guarantee marks (2009)
- FTC Jewelry Guides, 16 CFR 23.6 (platinum)
All sources are listed with the method on the sources page.