Short answer
A Fifty Fathoms heritage replica with a moon phase copies the Bathyscaphe Quantième Complet Phases de Lune. The layout is day and month windows under 12 o'clock, a date hand, and a moon disc at 6 o'clock. Case size is 43 mm on the steel model. The bezel insert is ceramic. The movement is a full calendar caliber, often built on the Valjoux 7751 layout. Street price runs from $250 to $600 for a steel case. Any water resistance number is a claim until the watch passes a pressure test.
fifty fathoms heritage replica watch price
What the original watch is
Blancpain released the Fifty Fathoms in 1953. French Navy combat swimmers asked for a watch they could read underwater and time a dive with. The answer was a rotating bezel with a 60-minute scale. Blancpain brought the Bathyscaphe name back to the catalog in 2013 and later added the Quantième Complet Phases de Lune. That model keeps the dive case and adds a complete calendar with a moon disc.
Fifty Fathoms Heritage Replica Watch with Perpetual Calendar Guide
Specs to compare
- Case: 43 mm for the steel complete calendar. The genuine case measures about 13 mm thick.
- Bezel: unidirectional, ceramic insert, 60-minute scale.
- Crystal: sapphire on the original, with antireflective coating on both faces.
- Dial: date hand with a serpentine tip, day and month apertures, moon disc at 6 o'clock.
- Movement: caliber 6654.P on the original, 72-hour power reserve.
- Water resistance: 300 m rating on the original.
Movement inside replicas
Full calendar moon phase calibers in replica builds come from two families. One follows the ETA 7751 layout, which is a chronograph base with day, date, month and moon phase. The other is a Seagull full calendar caliber. The 7751 layout adds two chronograph pushers that the original does not have. Look at the right case flank. The genuine watch has one crown. A case with pushers at 2 and 4 o'clock uses a chronograph base, which adds height and changes the profile.
Moon phase accuracy
A moon disc turns once per synodic month: 29 days, 12 hours, 44 minutes. The common 59-tooth gearing rounds that to 29.5 days. The disc drifts by one day about every two years and seven months. You reset it with the corrector, and you should not use the corrector between 9 p.m. and 3 a.m., when the calendar wheels are engaged.
Fifty Fathoms Heritage Replica Watch: Best Features to Look For
What to inspect before you pay
- Day and month discs. Both should sit centered in the apertures, with no cut-off letters.
- Date hand. It should jump at midnight, not creep from 10 p.m.
- Moon disc. It should advance one step per day, near midnight.
- Bezel. Firm detents, no back play, no gap between insert and case.
- Crown threads. Stainless threads strip fast when cross threaded. Turn the crown backward until it drops, then tighten.
- Case back engraving. Compare font weight and depth against photos of the original.
Water resistance
Gaskets, case back threads and crown seals vary by batch. A 300 m figure on a replica page is a copy of the original spec, not a test result. ISO 6425 defines dive watch criteria, including 100 m minimum depth rating and legibility in the dark. No replica seller publishes an ISO 6425 test report. Treat the watch as splash resistant until a watchmaker pressure tests it.
Price bands
- $80 to $150: mineral glass, printed moon disc, basic automatic caliber.
- $200 to $400: sapphire crystal, ceramic insert, Seagull or 7751 base.
- $450 to $700: better case finishing, screw-down crown, cleaner date hand.
The genuine steel Bathyscaphe Quantième Complet sells in five figures. The replica does not hold value and parts supply is uneven, so buy from a seller who stocks spare crowns and gaskets.
Notes on naming
"Heritage" is not a Blancpain model name for this watch. Sellers attach the word to Tribute to Fifty Fathoms pieces, which have different dials and no moon phase. If a listing uses heritage plus moon phase, check the photos against the Quantième Complet, not against a Tribute model. Case size, apertures and date hand placement are the three fastest tells.