How to Authenticate Pre-Owned Cartier Jewelry

All authentic Cartier gold pieces carry hallmarks on an inner surface — typically the inside of a bracelet band or the inner shank of a ring. The mark '750' indicates 18 karat gold (75% pure gold). '950' indicates platinum. These numbers are accompanied by Cartier's maker's mark.

Hallmarks are small and require a jeweler's loupe (10x magnification) to read clearly. On authentic Cartier, the stamps are precise and crisp — not blurry, shallow, or inconsistently sized. If you cannot read the hallmark clearly under magnification, have it examined by a professional jeweler before purchasing.

Country of origin hallmarks may also appear — French pieces carry the owl mark (eagle head for import) as a guarantee mark. These additional hallmarks are a positive sign but not required on all markets. Focus primarily on the '750' or '950' and the Cartier maker's mark.

Cartier has laser-engraved a serial number on all pieces produced after approximately 2000. The engraving appears on an interior surface: inside the bracelet band, inside the ring shank, on the clasp interior of a necklace.

The engraving is microscopic — not visible to the naked eye. A 10x jeweler's loupe is required. Under magnification, the characters should be sharp and uniform. The serial number format varies by collection but is always machine-precise.

This serial number is the piece's unique identifier and matches what appears in Cartier's certificate of authenticity. If a certificate is present, always verify that the number matches. If they don't match, either the certificate or the piece is not authentic.

Authentic Cartier jewelry uses solid metal — not hollow tubing or plated base metals. The weight of a genuine Cartier piece is immediately noticeable. A Love Bracelet in 18k gold should be substantial and feel dense in the hand.

The LOVE bracelet specifically: authentic versions weigh approximately 30-38g for a standard size in 18k yellow gold, depending on size and whether it has diamonds. The bracelet walls are thick and do not flex. Counterfeits often use thinner-walled construction that flexes slightly or feels light.

Compare the heft of a Trinity Ring, Love Ring, or any piece to what you expect from solid 18k gold. If it feels light or hollow when tapped lightly, it is not solid gold.

The signature screw detail on the Cartier Love Bracelet is one of the most scrutinized authentication points. Authentic Love Bracelet screws are slot-head (a single horizontal groove) — not Phillips or cross-head. This is critical: any Love Bracelet with Phillips-head screws is counterfeit.

When fully tightened, authentic screws sit flush with the bracelet surface. They do not protrude. The screw heads are uniform in size and the slot groove is precisely centered.

The screwdriver provided by Cartier matches the screw head exactly. If you are examining a piece with a screwdriver, it should engage smoothly and turn without any wobble or slipping.

Cartier issues a certificate of authenticity in a white booklet format. The serial number is printed inside and should match the laser engraving on the piece exactly. The certificate uses Cartier's typography consistently — the same font across all text.

Original Cartier packaging is a red box with gold Cartier logo on the lid. The box quality is high — sturdy, with precise closing mechanism and consistent red color. The interior has a white pillow or tray appropriate for the piece type.

Not all pre-owned Cartier will come with original certificate or box — that is normal and not an authentication failure. Authentication in the absence of certificate relies on hallmarks, laser engraving, and physical characteristics of the piece itself.