925 Plating, Hallmarks & Purity Stamps Explained (2026 Guide): 585, 750, 925 & Rhodium

What Is a Jewelry Hallmark?

I've checked hallmarks under a 10x loupe on thousands of pieces over ten years at José Lux, and it's one of the last things I look at before anything ships. A hallmark is a stamped mark that certifies a metal's purity, and often its maker or country of origin too. Spot a number like 585, 750, 925, or 925 Italy on a ring or chain, and you're looking at exactly that — read it right, and you know precisely what metal you're holding.

The Three Marks Hidden in One Stamp

That single stamp usually carries three separate pieces of information, even though it reads as one mark. We call the first the purity mark, which states the metal's fineness — 925, 750, 585. We call the second the maker's mark, a symbol or set of initials tied to whoever made the piece. And we call the third the assay or origin mark, which names the country that tested or manufactured it.

Where to Find the Hallmark on Your Piece

You'll find the stamp in a few predictable spots: inside a ring shank, along the inside edge of a clasp, or stamped into the post of an earring. On every José Lux piece, that spot holds a "925." We XRF-test every silver batch before it's approved for casting, then hallmark each finished piece so the stamp matches exactly what's inside it.

A hallmark exists for a reason. Now let's read the actual numbers stamped into yours.

Decoding Gold Purity Stamps — 585 and 750

We don't make gold jewelry at José Lux — we work exclusively in 925 sterling silver. But you might be holding a gold piece next to one of ours, or comparing two rings on the same tray, and those gold numbers still matter. Here's the honest scope on that: I'll walk you through 585 and 750 the same way I explain them to a customer standing at my bench.

What Does 585 Mean on Jewelry?

585 means 14K gold — 58.5% pure gold, or 14 of 24 parts gold, with the rest alloyed for strength. Pure 24K gold bends and scratches too easily for daily wear, so jewelers mix in metals like copper, silver, or zinc. 585 is the European hallmark form, and you'll see it stamped inside rings, bracelets, and pendant bails across the continent more often than in the US.

What Does 750 Mean on Jewelry?

750 means 18K gold — 75% pure gold, 25% alloy metals. It's purer than 585, and that extra purity makes it softer, too. An 18K prong holds a stone fine on day one, but it wears and scratches faster than a 14K prong under daily use. That trade-off between purity and durability runs through nearly every gold-purity decision a buyer makes.

Reading the Stamp — What "750" Looks Like on a Real Ring

Look inside the shank of a genuine 18K ring and you'll usually find tiny stamped numerals reading "750," sometimes no bigger than a grain of rice, often sitting beside a separate maker's mark or a small country-of-origin symbol. It's shallow, precise, and legible under a loupe. A blurry or hand-scratched "750" is a warning sign; a factory-stamped one sits crisp and even, cut to the same depth as the metal around it. I've turned away secondhand pieces at my own bench for exactly that reason.

Decoding Silver Purity Stamps — 925 and 925 Italy

I test every batch of silver we use with an XRF analyzer before it ever touches a casting mold, and here's what I'm checking for: 925 sterling silver is 92.5% pure silver (Ag) and 7.5% copper (Cu) — the copper is what keeps it strong enough to hold a stone setting. You'll see the US hallmark stamped as "925"; in Europe, it often reads ".925," the millesimal fineness version of the same mark. Both forms are recognized under US Federal Trade Commission (FTC) standards for metal purity, and both mean the same thing: 92.5 parts silver out of 1,000. For a deeper look at how that ratio holds up over years of wear, our complete guide to 925 sterling silver breaks down the full alloy, and this breakdown of the exact composition covers why 7.5% copper became the industry standard instead of a softer mix.

What Does 925 Mean on Jewelry?

925 is the baseline purity mark I described above — it certifies metal fineness, nothing more. If a piece is stamped 925 and nothing else, you're holding sterling silver. Full stop.

What Does 925 Italy Mean on Jewelry?

925 Italy isn't a separate or higher purity grade — it's the same 92.5% purity mark plus an Italian manufacturing-origin mark, stamped together as one mark. Last spring, a customer emailed me photos of a ring stamped "925 Italy" that she'd bought secondhand, worried the extra word meant something was off. It didn't. But I'll be honest with you here: a stamp alone never proves authenticity. I've seen faked "925 Italy" marks stamped into plain brass more than once. If you're not sure what you're holding, there's a real test for that, and I'll walk you through it in the next section.

585 vs. 750 vs. 925 vs. 925 Italy — Purity Stamps at a Glance

Knowing what 925 means is only half the picture. The next question is whether the piece in front of you is solid 925, or something wearing 925's name.

Solid Silver or Plated? What "925 Sterling Silver Plated" Really Means

Silver-plated and plated-over-925 sound almost identical, but they're not the same thing, and the difference matters more than any stamp alone tells you. Silver-plated usually means a cheap base metal — brass, nickel, or zinc alloy — wearing a thin silver skin over a core that isn't silver at all. Plated-over-925 means a genuine 925 silver core with a protective layer, like rhodium, on top. One is silver pretending to be more than it is. The other is silver, protected. It matters beyond looks, too — a thin silver skin can flake near a setting or a clasp within a year, while a plated-over-925 piece keeps its shape and its resale value even after the top layer eventually wears down.

How to Test If Your Piece Is Solid 925

Here's how I check which one I'm holding, and you can run the same tests at home, in order:

Once a piece checks out as solid 925, the next question isn't the silver anymore. It's what's plated on top of it.

What's Plated on Top of 925 Silver? Rhodium vs. 18K Gold

Every José Lux piece gets a Rhodium Plated White Gold Finish, hand-applied at our workshop in Hồ Chí Minh City, Vietnam. Rhodium is a platinum-group metal, atomic number 45, with a Mohs hardness of 6 — more than twice as hard as the 925 silver underneath, which sits at 2.5–3 — and roughly 80% reflectivity, which is what gives it that bright white shine you'd expect from white gold.

The process is electroplating, and it runs the same way on every batch. Surface activation cleans the piece electrolytically first. Then it goes into a rhodium bath — we use rhodium suspended in a phosphoric acid solution, which builds a thicker, more durable layer than the cheaper rhodium sulfate baths some suppliers use to cut cost. A distilled water rinse and a final visual inspection close out the process. I was at the workshop in November 2025 watching a batch come out of that bath, and the lead artisan pulled two rings back for a second pass because the coverage looked thin under his 20x scope. That's the standard we hold to: 0.5 to 1.0 microns, the international fine-jewelry benchmark, applied by hand in 20 to 30 minutes per piece, prep and inspection included. It's the same finish on the moissanite solitaire rings I set most often, and on our minimalist silver necklaces.

Is 925 Sterling Silver Gold-Plated Good? (The Vermeil Standard)

If you're comparing our silver against a gold-plated piece, the real benchmark is gold vermeil. The FTC's legal minimum for vermeil is 2.5 microns of 10-karat-or-better gold, electrolytically applied over a sterling silver base. Anything thinner isn't technically vermeil, whatever the listing calls it. I'll be straight with you: José Lux's own standard is the Rhodium Plated White Gold Finish, not gold vermeil. Different finish, different metal, and I'd rather you know exactly what you're buying than assume it's the same thing.

Rhodium vs. Gold Vermeil vs. Standard Gold Plating — Which Should You Choose?

A well-plated piece looks identical to solid metal on day one. The real test of quality is what happens after a year of wear.

Will the Plating Tarnish? Durability of Rhodium and 18K Gold on 925

I get this question more than almost any other in my inbox, so I'll answer it straight, no setup.

Does 925 Sterling Silver with Rhodium Plating Tarnish?

No — rhodium itself doesn't tarnish under normal wear. It's chemically inert to sulfur and oxygen, so it doesn't react the way bare silver does. Tarnish only becomes possible once the plating wears through to the 925 silver underneath, exposing the copper alloy to air again. Here's our real data, not a rounded-up marketing number: rated for 3 years under normal wear, typically closer to 5, and the longest recorded case on our books is 8 years. Tarnish complaints have sat near zero since we rolled the rhodium finish out across every piece we make in 2024, replacing the bare-silver approach we used before that.

Does 925 Sterling Silver with 18K Gold Plating Tarnish?

Gold itself doesn't tarnish either. But standard flash-plated gold, under half a micron thick, wears through fast. Once it does, the copper-alloyed silver underneath starts to tarnish just like any bare 925 piece would. Vermeil-thickness gold — 2.5 microns or more — holds up meaningfully longer than flash plating, though it still won't outlast a well-maintained rhodium finish in daily wear.

How Long Each Plating Type Actually Lasts

Every José Lux piece gets that replate done for free, for life. More on exactly how that works next.

Common Questions About Hallmarks, Plating, and Purity

Is "925 Italy" still real silver, or just a marketing stamp?

Yes, it's real silver. "925 Italy" combines a genuine purity mark (92.5% silver) with an Italian manufacturing-origin mark. It isn't a separate grade or a marketing add-on, though a stamp by itself never proves authenticity — a magnet test, weight check, or professional verification confirms it.

What's the difference between a hallmark and a trademark?

A hallmark certifies metal purity, and sometimes maker or origin, and is often required by law for precious metals sold above a certain weight. A trademark identifies a brand or company and protects its name legally. A piece can carry both marks at once, side by side, without either one replacing the other.

Which stamps mean solid metal, and which mean plated?

585, 750, 925, and 950 all indicate solid, purity-tested metal. HGE, GP, GF, and "vermeil" indicate a plated or filled piece over a different base metal. The two groups aren't interchangeable, and confusing them is one of the most common jewelry-buying mistakes.

Rhodium or 18K gold plating — which lasts longer for everyday wear?

Rhodium generally outlasts standard gold plating in daily wear, with a typical 5-year lifespan against flash gold plating's several months to a year. Vermeil-thickness gold narrows that gap but still trails rhodium's realistic durability under normal, daily conditions.

Protecting the Mark — Care That Keeps 925 Jewelry Looking Genuine

Reading a hallmark tells you what a piece is supposed to be. Protecting it is what keeps that promise true years later.

Daily Habits That Slow Tarnish

When to Replate vs. When to Retire the Piece

Once the rhodium finish wears through — most of our customers see 5 years or more — ship the piece back and we'll replate it for free, covered under the lifetime warranty for as long as you own it. That warranty doesn't stretch to cover everything, though: genuine structural damage, like a bent shank or a cracked setting from an impact, falls outside its scope. That's a retire-and-repair conversation, not a replate, and I'd rather tell you that now than after you've shipped something in expecting a free fix it wasn't built to cover.

That's the other half of what a stamp inside the band is telling you: what a piece is, and what it takes to keep it that way. Whether you're holding a José Lux ring or checking a secondhand find, the mark and the maintenance go together.