To tell real 925 sterling silver, start with the number: 925 parts per thousand, or 92.5% silver by weight, with the rest usually copper. A 925 stamp is a claim, by whoever applied it, that the metal meets that standard. A magnet and a scale can flag a suspect piece at home, but confirming the silver content takes professional testing.
We've sold silver jewelry since 2004. Every piece we sell comes from manufacturers in Thailand, and every silver piece carries a 925 stamp. So this page covers where that stamp sits on our pieces, what the home checks can and can't show, what our rings and pendants weigh, and which parts of some designs are brass, copper or plating.
What Does 925 Mean on Silver Jewelry?
Sterling silver has a fineness standard of 92.5% silver by weight, usually alloyed with copper. In the US, the FTC's Jewelry Guides set sterling at a minimum of 925 parts per thousand, with small tolerances written into federal law.
So yes, 925 is real silver: it's 92.5% silver, alloyed and not pure. Both metals in the alloy react with sulfur in the air, which is why sterling can darken over time. Our page on why silver turns black explains the chemistry and how we tell customers to clean it.
Where the 925 Stamp Is on Our Pieces
On our rings, the stamp is inside the band. On pendants, it's on the back. Every silver piece we sell has one.
A stamp is a claim, though, not a test result. In the US, a quality mark is applied by the maker or seller, and the law doesn't require an independent assay first. The UK works differently: silver articles of 7.78 g or more generally need a hallmark from an assay office. That's why this page calls the mark on our pieces a 925 stamp, not a hallmark.
We've never come across a fake 925 piece from our manufacturers. If you ever have doubts about a piece you bought from us, write to support@bikerringshop.com and tell us what you're seeing.
Home Checks: What a Magnet and a Scale Can Tell You
A magnet is the quickest check. Silver and copper aren't magnetic, so sterling shouldn't jump to one. A strong pull means there's magnetic metal somewhere in the piece. If only a small part such as the clasp reacts, that doesn't make the whole piece fake. And no pull doesn't prove silver, because brass and copper don't pull either.
Sterling silver is heavier than stainless steel for the same volume of metal, so weight gives you a hint. Sterling is about 10.36 g/cm³, against 8.0 g/cm³ for 316L stainless steel. For equal volumes of metal, 316L weighs about 23% less, so a steel ring with exactly the same volume of metal as a 20 g sterling ring would come in around 15.4 g. Common brass is less dense than sterling too, though its density depends on the grade. Stones, hollow backs and different proportions all move the numbers, so a scale can raise a question but can't settle it.
Tarnish and green marks don't settle it either. Real sterling can tarnish, and metals that contain copper can sometimes leave a green mark on skin, so neither one tells you whether a piece is genuine.
What does confirm it is professional testing, and the tester should choose the method: the Sheffield Assay Office offers instrumental analysis including XRF, and the London Assay Office notes that heavy plating can affect XRF readings and that traditional testing scratches or removes a sample. Density on its own doesn't certify 925.
How Much Does a Silver Ring Weigh? What Ours Weigh
We weigh our pieces on a jewelry scale and put the weight on the product page. On October 19, 2026, 443 of the 448 sterling silver rings in our live catalog listed a weight. Half of them weighed 20 g or less and nine in ten weighed 31 g or less. The lightest, a slim evil-eye band, weighs 2 g; the heaviest are three dragon rings at 78 g, among them the full-finger Eastern Dragon Ring.
Pendants run lighter. 276 of our 277 sterling pendants listed a weight, with a median of 15.5 g and nine in ten at 30 g or less.
To work out how much silver is in a ring that's all sterling, multiply its weight by 0.925: a 20 g ring holds about 18.5 g. The 78 g dragon holds at most about 72 g, because its two red CZ eyes aren't silver. A listed weight is the finished piece, stones and any other parts included, so take those out before you multiply.
Which Parts of Our Pieces Aren't Silver?
Some of our designs mix metals on purpose, and most listings name those metals in the title or description. A few only say gold-tone, so if you can't tell which part is which, ask us. The table shows what you'll find next to the sterling, counted from the titles of our active listings on October 19, 2026.
| Material | Where it shows up | What to know |
|---|---|---|
| Solid brass | The yellow parts of some two-tone pieces, like the cross on our crusader cross ring; 69 listings name sterling silver and brass | Brass is a copper alloy, mostly copper and zinc, so it can darken with time, and the copper in it can sometimes leave a green mark on skin. |
| Copper | Copper parts in 20 listings, 12 of them with brass as well | Copper darkens too, and it can also leave a green mark. |
| Gold plating | 23 listings name gold plating or gold over silver, about half of them bishop rings and cross designs; one of them is a gold-plated brass skull ring | Under the FTC Guides, vermeil needs gold of at least 10K, at least 2.5 microns of fine gold thick. Where a listing states 3 microns of 14K gold, that's about 1.75 microns of fine gold; for the others we don't know the thickness, so none of it can be shown to meet that standard. |
| Silver plating over brass | Ten of our 46 wallet chains are brass; one of them, the Lion Head wallet chain, is plated in silver | It's labeled silver-plated brass in its description and priced very differently from sterling. |
| Cubic zirconia (CZ) | The clear or colored stones in 119 listings | A manufactured zirconium dioxide crystal, which a 1981 Gems & Gemology article on refractometers describes as optically clear and chemically inert. It adds to a piece's weight, not to its silver. |
If something on a listing isn't clear, ask us at support@bikerringshop.com before you order. Or browse our biker rings and sterling silver pendants, most of them with the weight on the page.