The short answer

A replica Breguet Classique moon phase is one of the harder watches to copy, and that cuts both ways. A good one is a slim gold dress watch with an engine-turned dial and a moon that tracks the lunar month. Most of what you find listed is not that. It is a 40mm case with a printed dial and a disc that spins once a day pretending to be the moon. The tell is mechanical. A real moon phase advances one step every 24 hours and 50 minutes, so the moon disc needs its own reduction gearing, normally a 59-tooth disc driven off the hour wheel. If the moon rides directly on the hour hand, or the watch has a quartz movement, you are looking at a day and night indicator wearing a moon phase costume. Photos of the movement answer this faster than any description in a listing.

What the genuine watch actually is

The reference almost every copy chases is the Classique 7787, a 39mm gold dress watch with a self-winding movement, a power reserve sector at 12 o'clock, and the moon phase aperture in the upper half of the dial. The originals use hand-guilloché dial work, blued steel Breguet hands with the eccentric hollowed tips, a rail-track chapter ring, and the brand's secret signature engraved into the dial edge. The calibre is a thin Breguet movement developed from a Frederic Piguet base, and the finishing is the whole point: hand-bevelled bridges, polished and chamfered screw heads, an engraved balance cock, a level of decoration done by people, not machines.

That combination is what makes the watch worth what it costs, and it is also what makes it nearly impossible to reproduce at replica prices. You are not buying a design when you buy the real thing. You are buying a hundred hours of hand work on a surface the size of a coin.

Where the copies fall apart

The moon phase itself

This is the first thing I check and the fastest way to separate tiers. Cheap builds mount the moon disc on the hour wheel, so it completes a full turn every 24 hours. That is a day and night wheel, nothing more. Mid-tier builds sometimes add a 29.5-day reduction but use a stamped brass disc with a rough blue finish, and the moon itself looks like a sticker. Better builds use a silvered or gilt moon against a dark sky, sometimes with small stars, and the aperture is cut clean instead of punched. Even then, the alignment is often wrong. A real moon phase shows the correct phase for the date when you set it, and the jump happens once per lunar day, quietly, at roughly the same time each evening.

The dial

Guilloché is the giveaway. Genuine engine turning is cut by a rose engine and leaves crisp, deep grooves with sharp edges and a slight sheen that shifts as you tilt the watch. Stamped or printed patterns look flat, and under a loupe the lines are rounded and shallow. On replicas the chapter ring is often printed slightly off center, the numerals lose their serifs, and the secret signature is either missing or blown up to the point where it reads as a brand stamp. Breguet hands are another weak spot. The real ones are heat-blued steel with a hollowed eccentric tip, thin and perfectly proportioned. Copies are usually too thick, too shiny, and painted rather than blued.

The case and finish

Most replicas are steel with gold plating or a gold-tone PVD layer. The plating wears through at the lugs and the caseback threads within a year or two of regular wear, and once it goes, no polisher can bring it back. Case proportions matter too. The real 7787 is 39mm across and thin, around 10.2mm, because the movement is a slim dress calibre. Many copies are 40 to 42mm and noticeably thicker, and the extra height comes from a movement that was never designed to sit in a dress watch case.

Price tiers, roughly

• Under $150: quartz in almost every case, day and night disc instead of a moon phase, plated brass or zinc alloy cases, mineral glass. These fall apart and cannot be repaired.
• $250 to $500: an automatic Asian movement, sometimes with a real 29.5-day moon module, stamped dial, steel case with plating. This is where most of the market sits.
• $600 to $1,200: better case finishing, sapphire crystal, a modified ETA-style or high-grade Asian clone movement, tighter dial printing, occasionally a genuine guilloché pattern cut by machine. Still not close to the original in hand.

Legal reality in the United States

Counterfeit branded watches are illegal to import into the US. Customs and Border Protection seizes them, and a package can be pulled even when a single watch is bought for personal use. Selling or trafficking in counterfeit goods carries civil liability and criminal penalties, and the exposure grows fast if you buy, then flip. A watch you cannot legally resell, cannot insure, and cannot declare is not a collectible. It is inventory with a countdown on it.

Service, repairs, and resale

A real watchmaker will not touch a counterfeit. Parts are unavailable, technical documentation does not exist, and the moon phase module on a cheap copy is often a plastic wheel pressed onto a brass pin. When it stops, it stays stopped. Add up the purchase price and the cost of a repair you cannot get, and the math on these watches is worse than the math on a serviceable watch from an independent brand. Resale is close to zero, and brand-name auction houses and forums will remove listings.

A short checklist if you keep looking

1. Ask for the movement name and a clear photo of the caseback and movement. No photo, no deal.
2. Confirm the moon phase advances once per lunar day, not once per 24 hours.
3. Ask about the moon disc material: silvered metal or printed plastic.
4. Check case diameter and thickness against the reference you want.
5. Look at the dial pattern at 10x. Crisp grooves mean engine turning. Soft, flat lines mean stamping.
6. Assume the plating will wear and factor that into what you are willing to pay.

If what you want is the look

The honest alternative is a moon phase watch from a small independent brand. You can find Swiss or Japanese mechanical moon phase watches between $300 and $800 with a real astronomical complication, a serviceable movement, and a warranty. They will not say Breguet on the dial, and that is the point. You get the complication, the proportions, and a watch a watchmaker will actually open. If the appeal is the name on the dial, no replica solves that. Everyone who matters in a watch conversation reads the hands, the guilloché, and the thickness before they read the signature.