Short answer

A fake Breguet in yellow gold is a replica watch with a gold-tone case. Most use brass or 316L stainless steel under a gold coating. Plating thickness runs from 0.3 microns on cheap units to 5 microns on better ones. Real Breguet yellow gold cases are 18k solid gold, 750 parts per thousand. A replica weighs less and has no assay mark inside the caseback.

Plating types on the market

Three finishes show up in replica listings.

  • PVD coating. Titanium nitride or zirconium nitride. Thickness 0.3 to 1 micron. Color matches 18k yellow gold on day one. It wears at edges, crown threads, and clasp tips.
  • Electroplated gold. 1 to 5 microns of gold over nickel or brass. US trade rule 16 CFR 23.4 sets 175 microinches, about 4.4 microns, as the floor for the term “gold plated.” Few replicas reach that floor.
  • Gold filled or vermeil. A bonded layer of 10k to 18k gold on a base metal core. Rare in replicas. Common in vintage dress watches.

Breguet case codes

Breguet prints the case metal in the reference number. BA is yellow gold, BB is white gold, BR is rose gold, PT is platinum, ST is steel. A listing that says 5177BA claims a yellow gold case. On a replica the suffix is a label, not a metal spec. A genuine 18k caseback carries a Swiss assay mark, the St. Bernard head for 18k gold, the 750 stamp, and the Breguet serial. Replicas carry laser etching or nothing at all.

Models copied in yellow gold

  • Classique 5157 and 5177. 38 mm round case. Guilloché dial with hobnail pattern.
  • Marine 5817. 39 mm case. Rubber or leather strap.
  • Tradition 7057. 40 mm case. Exposed movement bridges on the dial side.
  • Reine de Naples 8928. Oval case, 33 x 24.95 mm.

Reference numbers change with dial and bracelet. A seller who lists one number for five dial options is guessing.

Movement and weight

Better replicas use an ETA 2824 clone, a Miyota 9015, or a Seagull ST18. Cheap units use a 21-jewel DG2813. Movement choice does not change the case metal. Gold density is 15.5 g/cm3. Steel is 7.9 g/cm3. The same case shape in 18k gold weighs close to double the steel version. A scale is the fastest test.

Checks before you buy

  1. Look at the caseback rim. Solid gold shows a crisp assay mark. Plating hides the mark or shows it stamped on top of the coating.
  2. Rub the case edge. Plating dulls where a wrist rubs. Solid gold keeps color.
  3. Inspect the crown and lugs. Plated brass pits. Gold does not rust.
  4. Ask for a scale photo. A dealer who will not post one has a plated case.
  5. Check the weight claim. A 38 mm yellow gold case lands near 25 to 30 grams alone. A plated case lands near 12 to 15 grams.

US legal status

18 U.S.C. 2320 makes trafficking in counterfeit goods a federal crime. A first offense carries up to 10 years in prison and a $2 million fine for an individual. US Customs and Border Protection seizes counterfeit watches at mail and express consignment hubs. Breguet holds US trademark registrations for the name and the dial layout. A replica with the Breguet name and logo is counterfeit under that statute. A gold-tone watch with no brand marks falls under different rules.

Common buyer questions

Does yellow gold plating turn green? Copper or brass under gold reacts with sweat and leaves a green mark on skin. Solid 18k gold does not. Will a jeweler test it? A jeweler with an X-ray fluorescence gun reads surface content in seconds. Plated cases read gold on the surface and copper or nickel underneath. Unknown: exact plating specs for any single factory batch. Sellers do not publish them.