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The Aqua Terra Worldtimer displays all 24 time zones on a single dial with co-axial movement finishing; strong technical value at a price well below comparable Swiss GMT watches.

Mass-producedbest value#3 in familyOfficial press photos

Condition affects price

Pre-owned watches trade across a wide condition spectrum. These ranges are typical for the secondary market.

New Old Stock
Unworn example retaining original packaging, tags, and warranty documentation.
+30–50% vs median
Unpolished
Worn but the case has never been polished; original brushed and polished surfaces are intact.
+15–25% vs median
Polished
Case has been professionally or amateur polished at some point; edge definition is softened.
-15 to -5% vs median
Recently Serviced
Movement has been recently serviced with documented service records; case condition varies.
At median
Project
Needs service, has dial or hand issues, non-original parts, or other remediation before daily wear.
-50 to -25% vs median

Full condition grading guide →

Market price

$4,500$6,500
steel·2026 Q2
Price trend chart coming soon

The Aqua Terra Worldtimer with all-24-timezone display and Master Chronometer certification offers a technical specification that few competitors match at the price; secondary prices track just below retail.

Editorial estimate, 2026 Q2. Actual prices vary by condition, date, and box/papers status.

In-house manufacture caliber · caliber Omega Cal. 8938: Co-Axial Master Chronometer with GMT, 25,200bph, 55h PR, 38j; METAS-certified, anti-magnetic to 15,000 gauss; Aqua Terra GMT caliber · 55h power reserve (2.3 days)
Large case: suits wrists 7 in+ (18 cm+)
43 mm case. A bold, statement-size wear. Best suited to larger wrists where the case sits flush.

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Authentication

Cal. 8605 METAS certification and vertical "teak" dial lines authenticate the Aqua Terra GMT against standard Aqua Terra references

Known issues in the market
  • METAS "Master Chronometer" certification is verifiable via Omega's serial lookup and should appear on the caseback
  • "Teak" vertical stripes on the dial are a defining design element; absence indicates a different Aqua Terra reference
  • GMT complication means an additional hand; verify four hands are present (hours, minutes, GMT, seconds)
AreaWhat to checkWhat is correctRed flag
dialVertical teak lines and GMT designationVertical brushed lines on dial surface creating "teak" wood texture; "Co-Axial Master Chronometer" text; "GMT" designation; four-hand layout visible (hours, minutes, GMT, seconds); "Aqua Terra" text; "Omega" at 12Smooth or horizontal-grain dial (different Aqua Terra variant); missing "GMT" text; only three hands visible; "Co-Axial" without "Master Chronometer" on METAS variant
movementCal. 8605 via caseback"Cal. 8605" on movement visible through exhibition caseback; co-axial escapement; "Master Chronometer" METAS certification; silicon balance spring; "Omega" signed; anti-magnetic to 15,000 gaussCal. 8500 or 8501 (non-GMT variants); ETA-based movement in claimed METAS variant; caseback without METAS certification text; exhibition back absent
casebackMETAS certification marking"Master Chronometer Certified" text; "15,000 gauss" antimagnetic rating; "METAS" logo or text; Omega medallion; serial number consistent with dial and movement signingNo METAS certification text; "COSC" only (earlier co-axial without METAS); caseback text inconsistent with claimed Cal. 8605 variant
Common legitimate replacements
  • Stainless steel bracelet with polished center links is standard; aftermarket rubber or leather straps are common secondary replacements.
  • Annual calendar complication on some variants adds date and month displays; verify claimed variant against dial layout.
Expert resources: Omega serial lookup at omegawatches.com confirms METAS certification and movement calibre. OmegaForums.net Aqua Terra section documents GMT variant production history.

Authentication guide

Last reviewed June 2026

The Aqua Terra Worldtimer adds a city-ring worldtime display to the standard Aqua Terra Teak-dial architecture. The worldtime ring is lacquered with city names and a rotating 24-hour disc -- the precision of the city-ring lettering and the correct city sequence are the fastest checks.

Known reproduction risks

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MEDIUM

Worldtime ring with incorrect city sequence or lettering

  • City names in wrong sequence for the 24-hour zone layout
  • Lettering blurry or incorrect weight under 5x magnification
  • City-ring color zones do not follow the Omega AM/PM palette

The Aqua Terra Worldtimer is not faked as frequently as the standard Aqua Terra, but the worldtime display is the first thing to verify carefully given its complexity.

Dial variants by era

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EraDescriptionIdentifiers
2017 to present (cal. 8938)Blue or silver Teak-pattern horizontal groove dial with an outer city-ring showing 24 world cities in correct sequence. The 24-hour disc rotates with the worldtime function. The OMEGA crown logo appears above 6 o'clock. The bezel is polished steel with no tachymeter or dive scale.
  • Outer city-ring with 24 cities in correct sequence and matching 24-hour disc
  • Horizontal Teak groove pattern on the main dial field
  • "Worldtimer" text on the dial confirming the complication
  • OMEGA crown logo above 6 o'clock, crisp and sharp
  • Polished steel bezel with no markings -- the Aqua Terra GMT does not use a rotating bezel
  • "CO-AXIAL MASTER CHRONOMETER" designation

Service part flags

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City-ring worldtime disc

Original: The worldtime function requires a city-ring with 24 correctly named and correctly sequenced cities aligned with a 24-hour disc. The city names are applied with Omega's specific typeface and are legible at arm's length. The disc colors (AM and PM zones) follow Omega's specific palette.

Replacement tells
  • City names in incorrect sequence or with the wrong city for a given time zone
  • City-ring lettering blurry or inconsistent in weight -- original is crisply applied
  • Color zones on the 24-hour disc incorrect for Omega specification
  • City ring spins independently of the crown-advance function -- should advance in one-city increments
Teak groove dial

Original: Same horizontal groove specification as the standard Aqua Terra -- consistent depth and spacing across the entire dial field. On the GMT, the main dial occupies the central field with the worldtime ring forming the outer chapter ring.

Replacement tells
  • Groove depth inconsistent between the main field and the area adjacent to the worldtime ring
  • Any interruption or irregularity in the groove pattern at the city-ring junction

Case back markings

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2017 to present
  • Caliber 8938 designation
  • "CO-AXIAL MASTER CHRONOMETER" text
  • "150 M / 500 FT" water resistance
  • METAS certification reference
  • "OMEGA" and "SWISS MADE"
  • Case reference and serial number

Movement tells

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  • Cal. 8938 is a Master Chronometer GMT with anti-magnetic silicon balance spring. The worldtime function advances via the crown in one-city increments; the mechanism should be precise and click into position cleanly without any slip or over-advance.
  • Power reserve is approximately 55 hours. The automatic winding is bidirectional.
  • The co-axial escapement geometry applies: visible on display-back examples as the three-level co-axial wheel at approximately the 6 o'clock position of the movement. No standard lever escapement would replicate this geometry.
Sources: Omega Aqua Terra official; Hodinkee Aqua Terra Worldtimer review.

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