Jewelry
Reading Silver Marks: 925, Sterling, and What the Law Requires
Sterling is a legal floor of 92.5 percent silver, coin silver is 900, and plate must say plate — the FTC guides police the words, while hallmarks are the oldest verification system in jewelry.
By Claire Donovan · Published Oct 8, 2026 · Updated Oct 8, 2026
The short version
Sterling is a legal floor of 92.5 percent silver, coin silver is 900, and plate must say plate — the FTC guides police the words, while hallmarks are the oldest verification system in jewelry.
Every label term in this guide is explained in what the symbols actually mean .
Sterling is one of the few jewelry words with a legal floor under it, and the floor is specific: 92.5 percent silver by weight. The number comes from metallurgy rather than marketing — pure silver is too soft for a chain that takes daily stress, so centuries of practice settled on the 925 alloy, with copper as the standard hardener. What the law does with that number, and what it leaves to tradition, separates a stamp from a hallmark in ways worth knowing before any silver purchase.
What the FTC guides require
In the United States, the FTC’s guides for jewelry industry under 16 CFR Part 23 set the vocabulary. The word sterling, or the mark 925, may be used only on an alloy of at least 925 parts per thousand silver; coin silver means 900; and items below those thresholds cannot carry the qualifying words at all. Plated goods get their own discipline: a silver coating over base metal must be labeled silver plated, silver overlay, or electroplated, and the word silver alone implies the metal runs through. The guides also reach compound constructions: a plating thick enough to call overlay must meet defined minimums. This is the same labeling philosophy behind the gold-filled and vermeil thresholds: the regulator polices the nouns and the thresholds, and the buyer’s job is to notice which word the tag actually used.
The stamp is a claim; the hallmark is a finding
A 925 stamp is applied by the maker and attests to nothing but the maker’s word. A hallmark is the opposite: in Britain and several other jurisdictions, items must be sent to an assay office, tested for fineness, and struck with marks before sale. A full British hallmark reads as a small sentence — the lion passant for sterling, an assay office letter, a date letter placing the year, often a maker’s mark as well. That system, centuries old, is the closest thing jewelry has to independent lab verification, and it explains why vintage British silver carries resale confidence beyond most of the market. Britain also defines a purer standard: Britannia silver at 958. Continental marks differ — the 800, 875, 925 and 950 fineness numbers on European pieces — and Mexico stamps its own 925 with registry numbers.
Where the system fails, and how to check
The weakness of any stamp-based system is that stamps are cheap. Misstamped 925 on plated brass is common enough that the stamp alone should never close a purchase, particularly on marketplace listings and tourist-market pieces. The verification hierarchy is: hallmarks first, maker’s marks that can be traced second, and physical tests third. Weight is the quiet expert’s tool — silver is denser than the base metals used under plating, so a piece that feels light for its size is suspect. The magnet test catches only steel cores, since copper and brass are non-magnetic like silver, which makes it a one-way screen rather than proof. The long-term test is chemistry over time: sterling tarnishes and takes polish; plated base metal wears through at high points to show the color underneath, as the tarnish resistance piece’s salt-test logic shows.
The buying habit follows from the structure. Read the full mark, not the number: 925 with a traceable maker, or a hallmark set with office letters, is a defined alloy with a paper trail. 925 alone is a sentence with no witness — and on a piece priced like the metal inside it, an unwitnessed claim is worth exactly the doubt it leaves.
Claire Donovan
Spent eight years in womenswear buying before moving to editorial research. Reads care labels for fun and returns nothing without a wear log. How we rate.
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FAQ
- What does 925 actually guarantee?
- On an honest piece, that the alloy is at least 92.5 percent pure silver, with the remainder typically copper for hardness. Pure silver is too soft for rings and chains that take daily wear, so the standard exists to balance durability with value. The stamp itself, though, is only a maker's declaration — unlike a British hallmark, a lone 925 stamped anywhere in the world requires no independent testing and can be applied to anything.
- Can a plated item legally be called silver?
- Not alone. Under the FTC's jewelry guides, a product with a silver coating over base metal must be described as silver plated, silver overlay, or electroplated — the word silver standing by itself implies the metal throughout. The same logic that bans unqualified gold claims on plated goods applies here: qualified terms exist precisely so a shopper can tell a $3 plating from a $60 alloy by reading the label.
- How is a hallmark different from a stamp?
- A hallmark is applied by an independent assay office after testing the metal, not by the maker. British hallmarks combine a purity mark — the lion passant for sterling — with assay office letters and often a date letter and maker's mark, making them a traceable record rather than a claim. A plain 925 stamp tells you only what the manufacturer asserted; a hallmark tells you what a third party found.