The short answer
A fake Villeret moon phase stands or falls on the disc at 6 o'clock and the calendar layout built around it. If the two moons are the right color and sit on a properly graduated disc, and the day, date, and month all land where the original puts them, the watch reads correctly on the wrist from arm's length. Get those details wrong and no amount of case polishing hides it.
The watch everyone is copying is the Blancpain Villeret Quantième Complet, the complete calendar with the moon phase at six. Knowing that reference well is the whole game.
The moon phase disc is the give-away
I look at three things on the aperture: shape, color, and how the disc advances.
- Aperture shape. The opening should be a clean, symmetric arc that follows the curve of the dial printing. Cheap builds cut a rough rectangle or an off-center oval.
- Color. Deep navy blue with two gold or silver moons, plus small star marks. Washed-out purple, flat black, or a disc printed so dark you cannot see the stars are all signs of a low-tier build.
- How it moves. The disc should step forward roughly once a day, usually in a single jump. A moon that creeps continuously around the aperture, or sits visibly off-center between cycles, means the module underneath is crude.
Calendar layout and hands
Day and month sit in twin apertures below twelve, the date is read off a blued serpentine hand that sweeps around the dial edge, and the moon phase holds the bottom. The serpentine hand is the detail most fakes fumble: the curve should be smooth and the tip should reach the printed track without touching the minute track. Feuille-shaped hour and minute hands, applied Roman numerals, and an opaline dial finish round out the front.
Check the aperture edges for burrs and check that the date hand points at the actual date across a full month, not just on the first.
Case, bezel, crown, caseback
The reference case runs about 40 mm across with a slim profile and a stepped bezel that catches light in two bands. Lugs should curve down sharply toward the wrist. The correctors for day, date, month, and moon phase sit flush in the case band and need a pusher tool, not a fingernail. On the back you want a sapphire window, a decorated rotor, and engraving that is crisp rather than sandblasted flat.
- Thickness that balloons past roughly 12 mm usually means a thick generic movement crammed in.
- A crown that sits proud of the case or wobbles when you wind it.
- Engraving with blurry letters or a serial number stamped off-center.
What is actually inside
Most fakes use a Chinese automatic base with a calendar module bolted on top. That is fine if the module is built well, and it is where the money goes. Blancpain specs its own Villeret moon phase as needing correction about once every 122 years, thanks to a gear train that tracks the 29.53-day lunation closely. An ordinary 59-tooth moon phase gear runs a 29.5-day cycle and drifts about a day every two and a half to three years. Nobody expects the fake to match Blancpain's math, but the disc should at least hold alignment with the real lunar cycle for months, not days.
Setting and care
Never push the calendar correctors between roughly 9 p.m. and 3 a.m., when the mechanism is already engaging and the teeth are under load. Use the tool that came with the watch, push slowly, and set the moon phase once every few weeks rather than daily. Wind a non-worn watch once a week to keep the calendar advancing correctly.
Rough price bands
- Under $100. Quartz or basic automatic, printed moon disc, wrong proportions.
- $150 to $350. Decent automatic, correct layout, disc color varies.
- $400 and up. Closest case work, clean serpentine hand, disc that jumps on schedule.
What to ask a seller
Ask for a close-up of the moon aperture in daylight, a photo of the case band showing the correctors, and a short clip of the moon disc advancing. Ask what base movement is inside and whether the calendar module is a separate unit. A seller who answers those three questions with photos is usually a seller worth dealing with.