Breguet does not sell a model named the Marine Chronometer. The product line is called the Marine. Current references include the 5517, 5527, 5547, 5817, and 5847. Listings that use "Marine Chronometer" as a model name are a sign the watch is not from Breguet. Three checks settle most cases: the caliber, the serial numbers, and the dial finish.
Check the caliber
Breguet prints the caliber number on the movement and engraves the rotor with the Breguet name. Marine automatics run at 28,800 vibrations per hour, or 4 Hz. Known calibers: 517GG in the 5817, 777A in the 5517, 582QA in the 5527 chronograph, 519F/1 in the 5547, and 519R in the 5847 Marine Royale. A movement with a plain rotor, an ETA stamp, or no caliber number is not a Breguet movement.
Silicon parts appear in several Breguet calibers. The escape wheel and balance spring on those movements read black under light. A copy with steel pallet forks does not match.
Match the serial numbers
Breguet puts a serial number on the caseback and a matching number on the movement. Gold models carry a Swiss precious metal hallmark and the fineness mark "750" for 18k. Numbers must match across the case, the movement, and the certificate. A mismatch means the watch is built from parts, or the caseback was re-engraved.
Breguet keeps a record of serials. A boutique or a service center can confirm a number against the archive. The check costs nothing and takes a few days.
Inspect the dial and case
- Guilloche: the wave pattern on a genuine Marine dial is cut on an engine-turning lathe. Ridges are crisp and even. Copies show flat, shallow lines.
- Roman numerals: even spacing, even height, sharp edges.
- Hands: Breguet hands carry a hollow circle near the tip. Copies cut that circle off-center.
- Date window: centered in the aperture, with the numeral aligned to the frame.
- Case band: fluted, with even flutes and no machining marks between them.
- Water resistance: Breguet rates the 5517 at 300 m. Other Marine references sit lower.
Price and paperwork
A steel Marine 5517 three-hand sells used between about $16,000 and $20,000. Rose gold references run past $30,000. A sealed watch at $2,000 with a Breguet dial does not exist in this market. Boxes and papers add value, and both are copied with ease, so paper never replaces a serial check.
What the word chronometer means
Chronometer is a rate standard, not a model name. A movement certified as a chronometer passed a timed test at an observatory or a testing body. Breguet builds chronometer-grade movements. The Marine line includes no model called the Chronometer.
US legal position
US law treats a watch that carries a brand trademark without authorization as a counterfeit. Penalties sit in 18 U.S.C. Section 2320. The statute targets trafficking. Customs can seize shipments at import, and civil claims cover damages.
If you own one
- Do not polish the case. Polishing removes marks that identify the forgery.
- Photograph the caseback, the movement, and the certificate.
- Ask Breguet service to check the serial in the archive.
- Keep the receipt. A refund claim needs proof of purchase and a written opinion.
A watchmaker with a caseback tool can open a Marine in under a minute. That step answers more than any photo on a listing page.