A genuine Cartier piece passes six independent checks: crisp hallmarks (Cartier, 750 or PT950, the assay mark for its market), an individually engraved serial that matches its paperwork, screws that belong to the serial's era on a Love bracelet, the weight of solid 18k gold, model details that are precisely finished, and packaging that merely agrees. Replicas copy the look and even the serial; they rarely survive all six. Every piece in our authenticated pre-owned Cartier edit has.
- Hallmarks: Cartier + 750 (18k) or PT950 + the market's assay mark (eagle's head in France), crisply engraved.
- The serial must match the certificate — but copied serials exist, so it is one check of six.
- Love screws: flathead (early) → Phillips (transitional) → oval-logo flathead (current); era must match the serial.
- A size-17 yellow-gold Love weighs in the mid-30 g range; much lighter means plated base metal.
- Boxes and certificates are reproduced; only the metal and the marks count.
Why Cartier is one of the most-faked jewelry houses
Cartier is among the most counterfeited jewelry houses because its designs are instantly recognizable, its boutique prices are high, and its silhouettes are simple enough to imitate at a glance. The Love bracelet is the clearest example. A plain gold band with screw motifs is easy to copy in outline but difficult to reproduce in weight, engraving and finish.
The Love bracelet's icon status
Aldo Cipullo designed the Love bracelet for Cartier in New York in 1969. Its premise is a flat oval cuff that closes with screws and a dedicated screwdriver, meant to be worn continuously. More than five decades on, it remains the house's most recognizable jewelry design, and Juste un Clou, Trinity, Panthère and Clash share the same instant visibility.
That recognition carries a boutique price of several thousand dollars for plain 18k gold, and considerably more for diamond-set or platinum versions. A design that is both coveted and expensive draws counterfeiters.
Super-fakes with real-looking serials
The most convincing replicas go well beyond the shape. They carry a Cartier logo, a 750 purity mark and a serial number, and the serial is sometimes copied from a genuine piece. Many arrive with a red box, a pouch and a certificate.
A serial alone therefore proves very little. The same is true of packaging, which is reproduced at scale and sold separately.
What an authentication actually involves
Authentication is a cross-check. No single feature settles the question. Our specialists examine each piece against six independent checkpoints:
- Hallmark quality and placement
- Serial format, and whether it matches the paperwork
- Screw type relative to the serial's era
- Weight against solid 18k benchmarks
- Model-specific finishing, hinges and settings
- Whether the packaging agrees with the piece
A replica may pass one or two of these checks. It rarely passes all six together. That standard sits behind our Authenticity Guarantee, and the sections below explain each check.
Check 1: Hallmarks — Cartier, 750, PT950 and the eagle's head
Every genuine Cartier piece carries the Cartier name, a purity mark and an individually engraved serial, and the quality of that engraving is as telling as what it says. Our specialists read the marks under a loupe before anything else, because replicas most often fail here first.
Where the marks sit
On a Love bracelet the marks are engraved inside the band, with the size engraved beside the serial. On Juste un Clou they run along the inner curve. On a Trinity ring they appear inside one of the three bands, and on other rings inside the shank, with the European size.
A mark on the outside of a piece, or a missing mark on a band that should carry one, is a reason to stop and look closer.
Purity marks by metal
The purity mark tells you what the piece is made of, and it must agree with the metal in front of you.
- 750: 18k gold, meaning 75% pure gold. This is the standard mark on yellow, white and rose gold Cartier.
- 18K: an alternative way of stating the same 18k purity, seen on some pieces.
- PT950: platinum at 95% purity, used on platinum pieces.
Cartier's signature jewelry lines are made in solid 18k gold or platinum. A low-purity mark, or a piece marked 750 that feels light in the hand, does not fit the house.
Assay marks by market
Pieces sold in France carry the eagle's head, the French assay mark for 18k gold, beside the purity mark. Pieces sold elsewhere carry the assay marks of their own country, or none where national law does not require them.
The test is coherence. The assay mark should fit the country where the piece was sold, and that country should agree with any certificate or purchase record.
Engraving quality: what genuine looks like
Genuine Cartier engraving is crisp, deep, evenly spaced and consistent in stroke weight from the first letter to the last. Replica engraving tends to show one or more of these faults:
- Soft or shallow lettering that looks pressed or etched rather than cut
- Pitted or grainy grooves, often a sign of casting the mark into the piece
- Uneven spacing, drifting baselines or letters of inconsistent height
- A typeface that differs from the Cartier logotype
Decades of wear and professional polishing can soften genuine marks slightly. Even then, the letterforms stay regular and evenly spaced. Rough or irregular lettering does not come from age.
The hallmark reference table
The table below summarises each mark, what it means and where to find it.
| Mark | Meaning | Where |
|---|---|---|
| Cartier | Maker's mark | Inside band / inner curve |
| 750 | 18k gold (75%) | Beside the maker's mark |
| PT950 | Platinum (95%) | Platinum pieces |
| Eagle's head | French assay mark (France-sold pieces) | Beside purity mark |
| Serial (letters + digits) | Individual piece number | Inside band; matches certificate |
| Size (e.g. 17 / 52) | Bracelet or ring size | Beside serial |
Correct hallmarks are necessary but not sufficient. They establish that a piece is plausible, and the serial, screws and weight checks that follow establish whether it is real.
Check 2: The serial number and what it can and cannot prove
A serial number shows that a piece is consistent with genuine Cartier production. It cannot prove on its own that the piece is genuine. Our specialists treat it as one checkpoint of six, valuable mainly for what it confirms or contradicts elsewhere.
What a Cartier serial looks like
Modern Cartier serials are individually engraved and typically combine a letter prefix with digits. Formats have changed by era, so there is no single template. One common modern form is two letters followed by four digits.
The serial sits inside the band near the Cartier name and purity mark. It should match the depth, crispness and spacing of the hallmarks around it. A serial that looks lighter, newer or cut by a different hand than its neighbours deserves a closer look.
The size engraving
On bracelets, the size is engraved beside the serial as a simple number such as 17. Rings carry their size inside the band in European sizing, so a Trinity or Love ring will read 52 or 54 rather than a US size.
The engraved size should agree with the piece in hand. A bracelet marked 17 that measures noticeably larger or smaller, or a ring marked in US sizing, contradicts the rest of the evidence.
Why copied serials exist
Counterfeiters copy real serials from genuine pieces, online listings and certificates. The result is a replica carrying a number that passes a casual check, and a single real number can turn up on many fakes.
There is no public database for looking up Cartier serials, so a number cannot be verified online. A plausible serial proves only that whoever made the piece knew what a plausible serial looks like.
Matching the certificate
Where a warranty card or certificate survives, its serial and size must match the engraving exactly, character for character. One transposed digit or wrong letter is a mismatch, not a clerical slip.
Paperwork is also reproduced, so a match confirms only that the piece and its papers agree, not that either is authentic. A mismatch, however, is reason enough to stop the purchase. Before any piece joins our pre-owned Cartier bracelets, we read its serial against its hallmarks, era details, weight and any accompanying papers.
Check 3: Love bracelet screws by era
The screw head is one of the fastest ways to date a Love bracelet. Cartier has used three types: a plain flathead on early pieces, a Phillips-style cross head during a transitional period, and the current flathead set inside an oval logo surround. The screw type has to agree with the era indicated by the serial.
The three screw types
- Flathead (early production): a single straight slot, cleanly cut and centered in a flush head.
- Phillips-style (transitional): a cross-shaped recess, crisp at every arm, with no burring or rounding.
- Oval-logo flathead (current): a straight slot framed by an oval motif, the version found on modern production.
On all three, the head should sit level with the band and match the surrounding gold in color and polish. Our specialists also check that both screws on a bracelet are the same type and finish.
Why the era has to match the serial
A screw type that contradicts the serial's period is a red flag. A modern serial paired with Phillips screws, or an early-format serial paired with oval-logo screws, means some part of the piece does not belong with the rest. Replicas often get this wrong because they copy one reference photo for the screws and another for the engraving.
Common replica tells include round or sloppy heads, slots cut off-center, screws that sit proud of the band, and screws that do not function at all because the bracelet actually opens by another mechanism.
The screwdriver
Genuine Love screws open only with the matching Cartier screwdriver, which is shaped to the screw head. A bracelet that opens with a coin, a fingernail or a generic driver deserves close scrutiny. A missing screwdriver, however, is normal on pre-owned pieces and is not evidence against authenticity.
Replaced screws on pre-owned bracelets
Screws loosen and get lost over decades of wear, so replacements are part of the pre-owned reality. A bracelet serviced by Cartier may carry newer screws than its serial suggests, and service paperwork resolves that kind of mismatch. Without paperwork, our specialists treat a screw-era conflict as a reason to weigh the other five checks more heavily, never as something to ignore.
Check 4: Weight, finish and how gold wears
Solid 18k gold is dense, and a genuine Cartier piece feels it. A size-17 yellow-gold Love bracelet weighs in the mid-30-gram range; a piece that comes in markedly lighter is almost always plated base metal. Wear then confirms what the scale suggests, because real gold and plating age in very different ways.
Gram benchmarks
Weigh the bracelet complete, screws in place, on a jewellery scale that reads to 0.1 g. Our specialists treat the mid-30-gram benchmark for a size-17 yellow-gold Love as a blunt but effective filter: a few grams of variance can follow from size or polishing history, while a shortfall of a third or more cannot be explained away. Juste un Clou and Trinity pieces have the same solid heft, and a ring or bracelet that feels hollow or tinny in the hand deserves suspicion before any other check.
Plating wear
Plating is a thin surface layer, so it fails at the points of highest contact first. Look at the edges of the band, the screw heads, the nail tip of a Juste un Clou and the inner surface where the piece rests on skin. A change of colour in these spots, whether coppery, grey or silvery, means base metal is showing through. Solid 18k gold is the same colour all the way down.
Polishing lines vs deep scratches
Fine, multidirectional hairline marks are the normal signature of a worn gold bracelet. Deep gouges and dents are condition issues, not authenticity issues, and they are graded in our Condition Guide. Repeated professional polishing removes a little metal each time, which can soften the edges of the engraving and trim the weight slightly; read softened hallmarks on a heavily polished piece alongside its weight rather than in isolation.
How real 18k gold ages
- It develops a soft, satin-like patina of micro-scratches that diffuses the original high shine.
- It does not flake, peel, tarnish green or change colour at the edges.
- It can be polished back to a mirror finish because there is solid metal beneath the surface.
Check 5: Juste un Clou, Trinity, Panthère and Clash
Each Cartier line has its own failure points, and replicas fail on them predictably. On a Juste un Clou our specialists look at the nail head, tip and clasp. On a Trinity they test band movement, and on Panthère and Clash they examine every stone and bead setting under a loupe. All of this comes after the hallmark and weight checks, never instead of them.
Juste un Clou: the nail head, the tip and the click
A genuine Juste un Clou, Aldo Cipullo's 1971 nail design relaunched by Cartier in 2012, is finished like a precision tool. The nail head has clean, defined edges and the tip tapers evenly to a precise point. Replicas tend to show softened facets, a blunt or lopsided tip, or polishing compound trapped where head meets shank.
- Engraving: "Cartier" and 750 sit on the inner curve, crisp and evenly spaced like the Love hallmarks.
- Hinge and clasp: they close with a clean, positive click. A loose hinge, gritty action or visible gap at the closure is a common replica tell.
- Heft: solid 18k gold feels dense in the hand. A nail bracelet that feels hollow or springy deserves a scale.
Trinity: three bands that move as one
A genuine Trinity has three interlocking bands in white, yellow and rose gold that roll over one another freely and seamlessly. Louis Cartier's 1924 design depends on that movement. Roll the bands between your fingers: they should glide without catching, grinding or showing visible joins.
The engraving sits on the inside of one band, not spread across all three. Watch for replicas whose bands are soldered together, or whose three colours look like plating over a single metal. In those pieces the colour often wears through to a uniform base at the contact points. Our authenticated Cartier rings are each checked band by band.
Panthère and Clash: settings under magnification
On Panthère and Clash pieces, the settings matter as much as the metal. Pavé on a genuine Panthère is even, with stones level and uniformly spaced and every prong secure. The bead and stud motifs of Clash, launched in 2019, are regular in size and alignment. Each element should sit firmly and catch the light consistently.
Under a 10x loupe, replica pavé shows uneven stone heights, missing or bent prongs, and glue where metal should hold. Loose beads, rough edges between motifs or a rattle when the piece is shaken all point the same way. We apply the same scrutiny to every pendant in our Cartier necklaces edit.
Check 6: Boxes, certificates and era coherence
Boxes, pouches and certificates are the easiest part of a Cartier purchase to reproduce, so they can support an authentication but never decide it. Their real value is as a cross-check. Every detail on the paperwork must agree with what is engraved on the metal.
Why packaging proves nothing on its own
Replica sellers reproduce the red Cartier box, the pouch and the certificate alongside the jewelry, often convincingly. A complete set can make a fake look more credible than a genuine bracelet sold loose. Our specialists treat missing packaging as normal for pre-owned Cartier. A seller who offers the box as the proof is a reason to look harder at the piece itself.
Matching serials and sizes
When paperwork is present, the serial on the certificate or warranty card must match the engraving inside the band character for character. The size must agree too. A certificate for a size-17 bracelet cannot belong with a piece engraved 16. Any mismatch means the paperwork came from another piece or was made to accompany this one.
Era coherence: does everything tell the same story?
The strongest test is whether every element points to the same period and place. The serial format should fit the era the piece claims, and on a Love bracelet the screws should belong to that same era. The assay mark should also suit the market of sale, such as the eagle's head on a France-sold piece.
A single anomaly, such as a modern oval-logo screw on an earlier bracelet, needs a documented explanation before we accept it. Several anomalies together end the inquiry.
The six checks side by side
The table summarises how genuine Cartier and common replicas compare at each checkpoint. An authentic piece passes all six.
| Checkpoint | Genuine Cartier | Common replica tell |
|---|---|---|
| Hallmarks | Crisp, deep, even; correct purity and assay marks | Shallow, pitted, uneven, wrong purity |
| Serial | Era-correct format, matches certificate | Generic, mismatched or missing |
| Love screws | Type matches serial era; oval-logo on modern | Wrong type for era; round or sloppy heads |
| Weight | Solid 18k heft (mid-30 g size-17 YG Love) | Markedly light, plating wear |
| Finish | Precise edges, clean hinge/clasp click | Rough edges, loose hinge |
| Packaging | Matches serial and size | Offered as the proof |
Red flags: when to walk away
Walk away when a piece fails any one of the six checks. A genuine Cartier piece is coherent: its marks, serial, screws, weight and finish all tell the same story. One contradiction is enough reason to stop, however convincing the box or the seller.
The walk-away checklist
- Engraving that is shallow, soft, pitted or unevenly spaced.
- A missing or wrong purity mark, or an assay mark that does not fit the country of sale.
- A serial that is missing, generic, or differs from the certificate by even one character.
- Love screws whose head type contradicts the serial's era, or round, sloppy heads.
- A piece markedly lighter than solid 18k gold should be, or plating wearing through to another metal.
- Rough edges, a loose hinge, or a clasp that will not close with a clean click.
- Trinity bands that bind or catch; uneven or loose pavé on Panthère and Clash.
- A seller who presents the box, pouch or certificate as the proof.
Buying pre-owned Cartier with confidence
The safest way to buy pre-owned Cartier is from a seller whose specialists examine the physical piece, not photographs, against every check in this guide. Hallmarks, serial, screws, weight and finishing should all be confirmed before a piece is offered for sale.
Why buy authenticated
A replica with a copied serial and a convincing box can pass a quick inspection. It rarely passes six independent checks by someone who handles Cartier every day. Our specialists weigh, magnify and compare each piece against known production details, and every sale is backed by our Authenticity Guarantee.
Condition is graded separately from authenticity. You know whether the gold has been professionally polished or shows honest surface wear before you commit.
Where to start
- Love bracelet: the house's most recognisable design and the one most often copied. Confirm the engraved size, such as 17, against your wrist, because the oval sits close and cannot be resized. Browse authenticated examples among our Cartier bracelets.
- Juste un Clou: the natural partner to the Love. Look for a cleanly finished nail head and tip, and for marks on the inner curve.
- Trinity ring: three bands of white, yellow and rose gold that should roll freely. The European size is engraved inside, and our Cartier rings list it for every piece.
Explore further
For pieces beyond Cartier, our wider designer jewelry edit is authenticated to the same standard. Recently authenticated pieces appear first in new arrivals. If you are weighing a Tiffany piece alongside Cartier, our guide on how to authenticate Tiffany jewelry applies the same method to that house's marks.
Shop authenticated pre-owned Cartier
Frequently asked questions
How do I know if my Cartier Love bracelet is real?
Run six checks together, not one. Look for crisp, deep hallmarks inside the band: Cartier, 750 or PT950, and the assay mark for the country of sale. Confirm an individually engraved serial that matches any certificate. Check that the screw type fits the serial's era, and weigh it, since solid 18k gold has real heft. Finally, inspect the edges and hinge. Replicas often pass one or two checks but rarely all six.
What should a Cartier Love bracelet weigh?
A size-17 yellow-gold Love bracelet weighs in the mid-30-gram range. Larger sizes weigh more and smaller sizes less, and pieces set with diamonds or made in platinum, which is denser than gold, weigh more again. A piece that feels markedly light for its size is almost always plated base metal. Weight is a blunt test, but it quickly exposes the most common replicas. Use a calibrated jewellery scale that reads to at least 0.1 grams.
What do the numbers inside a Cartier bracelet mean?
Inside a Cartier bracelet you will usually find several marks. 750 is the purity mark for 18k gold, and PT950 marks platinum. The size, for example 17, is the bracelet size. The serial is a letter prefix plus digits, engraved individually for that piece. French-sold pieces also carry the eagle's head assay mark, while other markets carry their own. Every mark should be crisp, deep and evenly spaced. Soft or uneven engraving is a warning sign.
Does Cartier authenticate jewelry?
Cartier does not offer a public authentication service that issues verdicts or certificates for pre-owned pieces. Boutiques service and repair Cartier jewelry, and a boutique may decline a piece it does not recognise, but that is not a formal authentication. For a definitive assessment, use an independent specialist who examines hallmarks, serial, screws, weight and finishing in hand. Our specialists apply all six checks to every Cartier piece before it is offered for sale.
Is there a Cartier serial number lookup?
No public Cartier serial number database exists, so you cannot verify a serial online. A serial is still useful. It should follow an era-appropriate format, often a letter prefix plus digits, and it must match any warranty card or certificate exactly. Counterfeiters copy genuine serials from real pieces, so a plausible number proves nothing on its own. Treat the serial as one checkpoint alongside the hallmarks, screws, weight and finishing.
What screwdriver fits a Cartier Love bracelet?
Love bracelet screws open only with the matching Cartier screwdriver, which is made for the screw head of that bracelet's design. Generic jeweller's screwdrivers tend to slip and can scar the gold or strip the screw slot, so avoid improvising. Many pre-owned bracelets come without their original screwdriver, and on its own that is normal rather than a red flag. What matters more is that the screws themselves suit the bracelet's era.
Is 750 the same as 18k gold?
Yes. 750 means 750 parts per thousand pure gold, or 75 percent, which is exactly 18 out of 24 karats. Cartier stamps 750 on its 18k gold pieces, and some pieces are marked 18K instead. Platinum pieces carry PT950, meaning 95 percent platinum. A Cartier piece stamped with a lower purity, such as 585 or 14K, is inconsistent with the house's standard fine jewelry and should be examined very carefully.
Do Cartier rings have serial numbers?
Yes. Genuine Cartier rings, including the Love, Trinity and Juste un Clou, carry the Cartier name, a purity mark of 750 or PT950, and an individually engraved serial inside the band. The size is engraved in European sizing, for example 52. On a Trinity ring, the engraving sits on the inside of one of the three bands. As with bracelets, the serial should match any certificate, and the engraving should be crisp and evenly spaced.
Is it safe to buy a pre-owned Cartier Love bracelet?
Buying pre-owned is safe when an independent specialist has authenticated the piece in hand. Do not rely on photos, a box or a certificate alone. The risk comes from super-fakes that reproduce serials and packaging, which is why authentication must cover hallmarks, screws matched to era, weight and finishing. Buy from a seller who examines every piece and stands behind it with a written authenticity guarantee, and review the condition grading before purchase.
How much is a Cartier Love bracelet in 2026?
Cartier sets boutique prices and revises them periodically. The price depends on the metal (yellow, rose or white gold, or platinum), the width (classic or small), and whether the bracelet is set with diamonds. Pre-owned prices are typically below boutique retail and vary with condition, era, size and completeness, such as the original screwdriver and certificate. Check current boutique pricing for new pieces, and compare authenticated pre-owned listings with similar specifications.
Keep reading
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Browse all Collector Edit guides: authentication, buying guides, value and brand history.
Our in-house specialists physically inspect and verify every piece before it is listed, across the houses we carry.
Last reviewed: October 2026