A fake Rendez-Vous Moonphase My Star shows its hand in four places: the star marker, the moon disc, the moon phase gear train, and the case finish. Inspect them in that order. The star is the smallest detail on the dial and the hardest to copy, and the moon phase is the hardest function to fake, because the disc has to advance one step per day and finish a full cycle in about 29.5 days.
Before you start
- A 10x jeweler's loupe
- Daylight or a 5000K desk lamp
- A white sheet of paper or white cloth
- A caliper and a small digital scale
- 24 hours of waiting time for the function test
Step-by-step inspection
- Place the watch on the white sheet under daylight or the lamp, dial up.
- Look at the star marker through the loupe and check the five points for sharp inner corners and clean edges.
- Tilt the case about 30 degrees and watch the star face shift from bright to dark in one clean pass, with no hazy patch in the middle.
- Study the moon disc under the loupe and confirm the surface shows crater detail with a soft gradient, not a flat silver circle or a printed blob.
- Check the aperture edge where the moon disc meets the dial, and confirm the rim is chamfered and even on all sides.
- Run a fingernail along the bezel and lugs and feel for a sharp lip or a step that should not be there.
- Check the dial texture with the loupe and confirm the lines run concentric and straight, with no waviness near the star window.
- Turn the crown to advance the moon phase and confirm the disc moves in one crisp step per full turn, not a slow creep.
- Set the moon to a known position, note the time, and wait 24 hours.
- Compare the disc after the wait and confirm it moved one step and no more.
- Weigh the head and measure the case with the caliper, then compare both numbers to the published spec for that version.
- Check the crown signature, thread feel, and diameter against the case size.
- Inspect the caseback engraving with the loupe and confirm the lettering has depth, clean walls, and even spacing.
- Check the strap stitching, edge paint, and buckle finish last.
What the star marker should look like
On the genuine Rendez-Vous Moonphase, the star sits with the moon display and reads as a separate element set into the dial, with a polished top face and defined points. A high-grade replica gets close on shape but often loses the polish, so the star looks dull next to the hands. A cheap fake shows rounded points, visible stamping marks, and a star that is slightly too large or sits off center in its window.
Moon phase function test
Many fakes use a 24-hour disc or a printed moon that never moves on its own. A real moon phase runs from a 59-tooth disc that drives the display through a full cycle in one synodic month. Set the moon at a known position, wait a full day, and confirm a single step. Repeat for three days if you want a firmer answer. If the disc drifts two steps, stalls, or jumps when you shake the watch, the module is a decorative part, not a working complication.
Where replicas fail
- Star points rounded or stamped instead of polished
- Moon disc printed flat, with no crater shading
- Moon phase that does not track a 29.5 day cycle
- Caseback engraving shallow or filled with polish
- Dial texture that waves near the aperture
- Crown that sits proud of the case or feels gritty
Work the list in order and you will sort a serious replica from a costume piece in under an hour, plus the 24-hour wait.