Answer
A fake Constellation 131.23 is a counterfeit watch stamped with a real Omega reference number. Omega uses 131 for the Constellation family and 23 for a steel and gold two-tone case. A full reference has 11 digits, for example 131.23.34.20.55.001. The digits prove nothing on their own. Omega publishes its reference list, so replica sellers copy the numbers. You confirm a Constellation by the engraving on the case, the movement behind the sapphire caseback, the claw-shaped bezel parts, and the Master Chronometer card.
What the 131.23 group covers
- Family: Omega Constellation, current fifth generation, launched in 2018.
- Case and bracelet: stainless steel with gold. The digit pair 23 marks the two-tone combination. Listings describe the gold as Sedna or yellow. Confirm the tone on the Omega product page.
- Sizes: 34 mm and 36 mm cases in this group. Sapphire crystal front and back.
- Bezel: two half-moon claws, called griffes, at 3 and 9 o'clock. On diamond-set versions the claws sit outside the diamond ring.
- Movement: a Master Chronometer automatic calibre in the 8700 or 8800 range, co-axial escapement. The calibre number is stamped on the movement.
- Caseback: observatory medallion with eight stars.
Checks on a real 131.23
- Engraving. Omega cuts the reference and the serial number on the case with a laser. On current Constellations the marks sit between the lugs and on the caseback. Genuine engraving is crisp and shallow. Counterfeit engraving looks dot-matrix and uneven in depth.
- Movement. The display caseback shows the rotor, the balance, and the calibre number. The number on the movement matches the Master Chronometer card and the pictograms card.
- Claws and bezel. On two-tone models the claws are solid gold, not plated. Check the seam between claw and bezel. Fakes show a gap and a plating line.
- Bracelet and clasp. The bracelet integrates into the case. End links sit flush with no rattle. The clasp carries the Omega logo and the reference.
- Papers. Every Master Chronometer Omega ships with a card that lists the reference and serial and links to a METAS test result. The serial on the card must match the watch.
- Price. A genuine 34 mm or 36 mm two-tone Constellation lists in the thousands of USD at an Omega boutique. A listing that quotes a few hundred dollars describes a counterfeit, not a discount.
What photos cannot show
A photo cannot confirm case material, gold content, or movement. Gold content needs an X-ray fluorescence scan or a acid test. Movement identity needs the caseback off, which ends warranty service. Serial checks run through an Omega boutique or service center. If a seller will not send a photo of the engraving between the lugs, the deal has no basis.
Terms in replica listings
Sellers use Swiss replica, 1:1, super clone, and AAA for grades of counterfeit. None of these terms appear in the Omega catalog. A listing that pairs fake Constellation 131.23 with an 11-digit reference is reusing Omega data. Treat the number as an identifier for the real watch, not as proof of origin.