A fake Fifty Fathoms white gold is rarely gold. Most replicas sold under that label use a stainless steel case with rhodium or gold plating, and a smaller number use a tungsten alloy to copy the heft of 18k gold. Before you pay a gold premium, confirm three things: measured weight, caseback markings, and plating condition at the lugs and crown. If a seller cannot answer those three points in writing, treat the gold claim as decoration, not fact.
What Genuine White Gold Means on a Fifty Fathoms
Blancpain builds the Fifty Fathoms in stainless steel, titanium, and 18k white gold. The gold versions sit at the top of the range and share the dive case profile of the steel models, with the Bathyscaphe line offering a smaller gold option. White gold is an alloy of gold with white metals, and fine watchmakers finish it with rhodium for a bright white surface. That finish reads close to polished steel, so color alone will never identify the metal. Weight and hallmarks will.
Gold is dense. An 18k white gold case weighs close to twice what a steel case of identical dimensions weighs, which is the single hardest thing for a cheap replica to fake.
What Replica Makers Actually Use
- Gold plated steel: a steel case with a thin gold or titanium nitride layer. Light on the wrist, and the plating wears through at sharp edges.
- Rhodium plated steel: a brighter, harder finish that mimics the look of finished white gold without any gold content.
- Tungsten or tungsten alloy: heavy like gold and often used to pass a hand-weigh test. Tungsten is gray, so it still needs plating.
- Solid gold replicas: they exist, but they cost close to a used genuine steel watch and are rare on the open market.
How to Check a Replica Before You Buy
- Ask the seller to state the case material in writing, naming the metal and any plating thickness.
- Request the measured weight of the complete watch on a digital scale, with the strap or bracelet included.
- Compare that figure against a steel Fifty Fathoms of the same case size. A gold case should add a clear step up in mass.
- Ask for a macro photo of the caseback engraving and any hallmark stamps.
- Ask for macro photos of the lug tips, crown guards, and caseback edge under direct light, where plating wear shows first.
- Request a short video of the bezel turning, so you can judge click feel and back play.
- Confirm the movement type and whether the caseback is solid or display, since a display back changes what a buyer can verify.
Plating Wear Over Time
Plated cases fail in predictable places. Look at the inner edges of the lugs where a strap rubs, the crown threads, the caseback rim, and the bezel knurling. A dull yellow or gray patch against a bright white field means the plating is thin or already breached. Wiping the case with a soft cloth will not fix this, and polishing makes it worse by removing more of the layer.
Care Notes
Keep a plated replica away from chlorine, salt water, and abrasive cleaners. Rinse with fresh water after contact and dry with a microfiber cloth. Store it apart from other watches so the bracelet does not rub the case. If the plating has worn through to steel on a gold replica, no polishing compound will bring the color back.