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Mass-produced#6 in familyOfficial press photos

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In-house manufacture caliber · caliber Omega Cal. 8900: Co-Axial Master Chronometer automatic, 25,200bph, 60h PR, 39j; METAS-certified, anti-magnetic to 15,000 gauss; used in Aqua Terra and De Ville · 60h power reserve (2.5 days)

Also uses Omega Cal. 8900

Omega Seamaster Aqua Terra, 41mm Ref. 220.10.41.21.03.001, black dial, steel case
Omega
Seamaster Aqua Terra
Omega De Ville Hour Vision Ref. 433.13.41.21.03.001, black dial, steel case
Omega
De Ville
Large case: suits wrists 7 in+ (18 cm+)
43.5 mm case. A bold, statement-size wear. Best suited to larger wrists where the case sits flush.

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Authentication

The ceramic bezel insert condition is the primary value check; chips or repairs are immediately visible and substantially reduce value on this reference.

Known issues in the market
  • Ceramic bezel insert with chips, cracks, or replaced with aluminum insert; genuine Ceragold ceramic is more brittle than aluminum and chips rather than dents.
  • Helium escape valve at 10 o'clock blocked or removed; the HEV is a functional component and its absence or modification is a red flag.
  • Cal. 8900 replaced with non-METAS-certified movement; verify METAS documentation or test antimagnetic resistance if provenance is uncertain.
AreaWhat to checkWhat is correctRed flag
caseCeramic bezel insert integrityOne-piece ceramic insert is scratch-free from factory; color is uniform and deep; bezel numerals have correct Omega font; 60-click unidirectional rotationAny chip, crack, or repair on the ceramic insert; aluminum insert substituted for ceramic (different scratch resistance); loose bezel clicks
caseHelium escape valve at 10 o'clockHEV screws into the case at 10 o'clock; Omega-signed cap; valve unscrews smoothly; gasket shows no crackingMissing HEV; aftermarket replacement without Omega signing; HEV that is stuck or shows tool marks from forced operation
movementCal. 8900 Co-Axial Master ChronometerCal. 8900 visible through exhibition caseback; Co-Axial escapement; METAS certification to 15,000 gauss; Omega-signed rotorNon-Co-Axial escapement visible at caseback; movement without Omega rotor; movement inconsistent with Cal. 8900 architecture
crystalSapphire crystal with anti-reflective coatingDomed sapphire crystal; anti-reflective coating on both sides; Omega logo engraved at 6 o'clock position on crystal undersideMissing Omega logo engraving; crystal without anti-reflective coating; replacement crystal with different dome profile
braceletStainless bracelet with correct deployant claspOmega stainless bracelet with brushed center links and polished outer links; Omega-signed deployant clasp; diver extension in clasp for wetsuitNon-Omega deployant clasp; missing diver extension; bracelet without correct link finishing pattern
Common legitimate replacements
  • Ceramic bezel inserts are replaced after chipping; verify replacement is genuine Omega Ceragold, not a third-party insert.
  • Bracelets are frequently replaced; diver extension in clasp is a specific Planet Ocean feature to verify.
  • Crystals are replaced during service; Omega crystal with correct logo engraving is required.
Expert resources: OmegaForums.net Planet Ocean technical threads. Omega Museum serial database. Ceramic vs aluminum bezel identification guide (ceramic has different scratch pattern under loupe). METAS certification number can be cross-referenced with Omega service records.

Authentication guide

Last reviewed June 2026

The Planet Ocean's two-finish case -- brushed sides, polished flanks -- is the fastest authenticity check. Polishing destroys the design intent and collapses the value. The ceramic bezel insert seating and co-axial movement inside are the technical anchors.

Known reproduction risks

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MEDIUM

Incorrect case-side finishing

  • Brushing direction inconsistent or absent on the main case body surfaces
  • Polished flanks show brushing marks -- the two-finish design has been lost
  • Case corners between brushed and polished surfaces are rounded rather than sharp

Case polishing is more common than outright counterfeiting on the Planet Ocean. A polished case on a watch asking for an unpolished price is misrepresentation.

MEDIUM

Ceramic bezel coloration and seating inconsistencies

  • Ceramic color is incorrect for the stated variant -- each colorway has a specific Omega palette
  • Bezel insert sits above or below the surround rather than flush
  • Bezel click count deviates from 120 positions
LOW

Generation misrepresentation

  • Caseback shows caliber 2500 on a watch sold as a Master Chronometer 9900 example
  • Dial lacks "Master Chronometer" text on a watch sold as current-generation

Dial variants by era

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EraDescriptionIdentifiers
2005 to 2011 (cal. 2500)First-generation Planet Ocean with cal. 2500 Co-Axial. Black dial with applied orange-tipped hands, orange seconds hand, and applied lume indices. The case finishing design is identical to later variants but the movement differs.
  • Black dial, applied luminescent indices
  • Orange accent on hour hand tip and orange seconds hand
  • "Planet Ocean" designation on dial
  • "Co-Axial" text present
  • No helical hairspring notation on first-generation examples
2011 to 2020 (cal. 8500/8501)Second generation with in-house caliber 8500 (non-COSC) or 8501 (COSC chronometer). Black and blue colorways most common; GMT variants exist with an additional hand. The co-axial wheel architecture is fully in-house from this generation forward.
  • "Co-Axial" designation on dial
  • "Chronometer" present on 8501 examples, absent on 8500
  • Orange seconds hand with applied lume indices
  • Polished flank surfaces on brushed main case body
  • Ceramic bezel insert with luminescent pip at 12
2020 to present (cal. 9900/9901)Current generation with cal. 9900/9901 Master Chronometer. Helical hairspring for anti-magnetic performance. Same external design language with Master Chronometer certification.
  • "Master Chronometer" designation on dial
  • "Co-Axial" text present
  • Caliber 9900 (non-COSC) or 9901 (COSC) -- check caseback for confirmation
  • Same two-finish case design as earlier generations

Service part flags

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Case finishing

Original: The Planet Ocean case has two distinct surface treatments. The top and sides of the main case body are brushed. The flanks (the beveled lower edges of the case) are polished to a mirror finish. This contrast is a deliberate design element and requires specific tools to preserve during service.

Replacement tells
  • Polished surfaces where brushing should be -- the transition between brushed and polished is blurry rather than sharp
  • Brushed surfaces where polishing should be -- flank surfaces that appear matte rather than mirrored
  • Consistent overall polish on the entire case -- the two-finish design has been collapsed by a polishing service
Ceramic bezel insert

Original: The unidirectional rotating bezel has a ceramic insert. The insert sits flush with the bezel surround with no visible gap. The luminescent pip at 12 should be evenly filled and aligned with the bezel center. Bezel tool marks (small scratches at 6 and 12 o'clock from a bezel-change tool) indicate the insert has been removed.

Replacement tells
  • Gap between the ceramic insert and the bezel surround -- any gap is incorrect
  • Bezel tool marks at 6 and 12 positions on the case
  • Luminescent pip off-center or with overflow beyond its recess
  • Ceramic coloration inconsistent with the genuine Omega palette -- fakes use cheaper ceramic with a different tonal quality
Crown

Original: Large helium-safe crown appropriate for the 600m diving specification. The crown is oversized relative to sports watches at shallower depths. Rubber gasket seals are internal. The crown has Omega knurling and logo.

Replacement tells
  • Crown smaller than correct proportion to case size
  • Knurling pattern inconsistent with Omega diving-crown standard
  • Crown logo not crisp or absent

Case back markings

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2005 to present
  • "600 m / 2000 ft" water resistance designation
  • Wave decoration on the solid caseback
  • "OMEGA" and "SWISS MADE" with OMEGA seal on some variants
  • Case reference number and serial number
  • Caliber designation matching the era (2500, 8500, 8501, 9900, or 9901)
  • Display casebacks exist on some variants -- caliber visible through sapphire window

Movement tells

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  • The co-axial escapement in all generations of the Planet Ocean uses a three-level co-axial wheel. On display-back variants this is visible; it is geometrically unlike a standard Swiss lever escapement. Any standard lever escapement visible through a display caseback indicates a movement swap.
  • The brushing direction on case surfaces should follow the case geometry consistently. Brushing that runs across the lug line or changes direction mid-surface was not applied at the factory.
  • Cal. 8500/8501 has a power reserve of approximately 60 hours; cal. 9900/9901 extends to 60 hours as well. The automatic winding is bidirectional. A watch that runs dry after 20 hours of inactivity has a mainspring or rotor issue.
  • GMT variants have an additional hour hand for a second time zone. Verify the GMT hand is present and correctly seated on its own cannon pinion -- missing hands or binding hands indicate incomplete assembly after service.
Sources: Omega Planet Ocean official; WatchUSeek Omega forum.

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