Short answer
A fake De Ville Trésor is a copy of Omega's dress watch. The genuine 40 mm Trésor uses a hand-wound movement, a sapphire caseback, and a case under 11 mm thick. Most copies get the dial close and fail on the movement. Open the caseback first. A rotor or a battery hatch is wrong for this model.
Genuine specs to compare
- Case sizes: 36 mm (quartz) and 40 mm (mechanical).
- Case thickness: about 10.5 mm on 40 mm references. Exact figures differ by reference, so check the number for the model you compare against.
- Lug width: 18 mm on 36 mm, 20 mm on 40 mm.
- Water resistance: 30 m, 3 bar.
- Crystal: domed sapphire front, sapphire back on mechanical models.
- Movement: Omega calibre 8910. Hand-wound, Co-Axial escapement, 72-hour power reserve.
- Certification: Master Chronometer, tested by METAS.
- Magnetic resistance: 15,000 gauss.
- Case metal: steel, or 18k gold in yellow, white, or Sedna.
Replica build tiers
Copies fall into three groups. Quartz copies sell for $50 to $150. The seconds hand jumps once per second. Mid-tier copies use an Asian automatic such as a Miyota 9015 or a Seagull. A rotor shows through the caseback, which no genuine Trésor has. High-tier copies use a hand-wound movement with plates shaped to imitate the 8910 layout. Listed prices for those run $300 to $600 on replica sites. Prices move, so treat the range as a guide and not a fixed number. Case thickness stays the weak point across all three groups.
Checks before you pay
- Caseback. The 40 mm Trésor shows a hand-wound movement through sapphire. No rotor. No battery hatch.
- Thickness. Use calipers. Copies run 1 mm to 2 mm thicker than the genuine case.
- Dial text. Check the accent on TRÉSOR and the line reading Co-Axial Master Chronometer. Look at letter spacing and font weight.
- Hands. Genuine hands are leaf-shaped with polished bevels. Copy hands show stamped edges and flat tops.
- Gold. Genuine gold cases are solid 18k. Replica gold is plating, often 3 to 5 microns, and it wears through on the lugs and crown.
- Crown action. Wind the crown. A quartz copy has nothing to wind. A hand-wound copy should run about 72 hours on a full wind. Many stop at 36 to 40 hours.
- Serial and reference. Genuine Omega serials run 8 digits on recent models. The caseback number should match the card and the movement.
Common tells
A date window at 3 o'clock is wrong. The Trésor has no date. A ticking seconds hand means quartz. Mineral glass scratches and lacks the dome of the genuine sapphire. Copy dials print Swiss Made with the wrong gap around the 6 o'clock marker. Caseback engraving on copies is shallow and laser-cut, not stamped. Lug holes sit in the wrong place on some copies, so a genuine 20 mm strap will not line up with the spring bars.
What no replica has
METAS Master Chronometer certification. Each certified Omega passes 8 tests and holds accuracy between 0 and +5 seconds a day. No replica carries that certificate or the test data behind it. Omega does not sell parts to the public, so repairs on a copy depend on the factory that built it. Water resistance on copies is untested. Do not swim with one. Movement service for a hand-wound copy can cost more than the watch.