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The Encyclopedia of Horology

Wristwatch · Triple date wristwatch with moon phases

Omega Cosmic Collector's Series Number Two

Partially verified

This Omega 'Cosmic' wristwatch, identified as Collector's Series Number Two from the Museum Collection, was manufactured in 2001. It is a square, self-winding timepiece housed in an 18K pink gold case, measuring 33.5 x 33 mm with a thickness of 11 mm. The watch features a triple date mechanism, displaying the day, month, and date, alongside a moon phase aperture located at the 6 o'clock position. The black dial is appointed with pink gold indexes and alpha-style hands. The movement is an Omega Caliber 2601, featuring a rhodium-plated finish with 'fausses côtes' decoration, 31 jewels, and a straight-line lever escapement. The balance is adjusted to 5 positions. The watch is completed with an 18K pink gold Omega buckle and retains its original sapphire crystal and water-resistant construction. The case back bears specific commemorative engravings related to the Museum Collection.

Front view of the Omega Cosmic Collector's Series Number Two, showing the black dial, calendar apertures, and pink gold case.
Front view of the Omega Cosmic Collector's Series Number Two, showing the black dial, calendar apertures, and pink gold case. — Antiquorum. Rights pending — permission not yet requested. Original source

Catalogue identity

Source
catalog.antiquorum.swiss
Category
Wristwatch · Triple date wristwatch with moon phases
Maker / attribution
Omega
Reference
BG 156.2001
Catalogue / lot identifier
254
Source-reported date
2001
Source-reported place
Switzerland
Source-reported serial
57977930

Source-reported attribution and specifications are not independent authentication. A listing does not establish present ownership, current display, availability or permission to reproduce.

Object description

Case and Dial Construction

The watch is housed in a three-body, 18K pink gold square case that has been finished with both polished and brushed surfaces. It features a concave bezel and stylized straight lugs, with functional pushers integrated into the band for adjusting the calendar complications. The case back is engraved with information regarding the Omega Museum Collection and the individual series number. The crystal is made of sapphire, providing water resistance to the assembly.

The dial is black, contrasted by applied pink gold indexes in baton, dagger, and pyramidal shapes. The calendar information is displayed through apertures for the day of the week and month, while the date is indicated by an outermost graduation featuring pink gold Arabic numerals. A subsidiary dial at the 6 o'clock position serves the moon phase display, and the time is indicated by pink gold alpha hands.

Evidence for this section
  • “C. Three-body, solid, polished and brushed, concave bezel, pushers in the band, stylized straight lugs”
  • “back numbered and engraved: ?1951, The Omega Museum Collection, COSMIC, Collector`s Series Number Two?, sapphire crystal.”
  • “D. Black with applied pink gold baton, dagger and pyramidal indexes”
  • “aperture for the moon phases at 6 o´clock, apertures for the day of the week, the month, and the phases of the moon”

Movement and Mechanics

Power is provided by the Omega Caliber 2601 self-winding movement. This caliber is rhodium-plated and features 'fausses côtes' decoration. The technical specifications include 31 jewels and a straight-line lever escapement. To ensure accuracy, the balance is monometallic and adjusted to 5 positions, paired with a self-compensating flat balance spring and a micrometer regulator.

The movement is signed, as are the dial and the case. The mechanism functions to drive the triple date and moon phase complications housed on the dial.

Evidence for this section
  • “M. Cal. 2601, rhodiumplated, ?fausses côtes? decoration, 31 jewels, straightline lever escapement”
  • “monometallic balance adjusted to 5 positions, shock absorber, selfcompensating flat balance spring, micrometer regulator.”
  • “Dial, case and movement signed.”
  • “Movement: 1* As new Overhaul recommended, at buyer's expense”

Provenance and Series Context

This watch is identified as the 'Collector's Series Number Two' originating from the Omega Museum Collection. The series is intended to reference the year 1951, as indicated by the '1951' marking on the case back. It is documented by the individual serial number 768/1951, indicating its specific production run within the Museum Collection series.

The watch was produced in 2001. The item is currently held by a Swiss collector and was presented for sale as a lot without a reserve price, reflecting its status as a collector's piece within the broader horological market.

Evidence for this section
  • “Collector`s Series Number Two from the Museum Collection. Made in 2001.”
  • “back numbered and engraved: ?1951, The Omega Museum Collection, COSMIC, Collector`s Series Number Two?”
  • “Accompanied by a guarantee (now void)”
  • “Property of an Swiss collector”

Open research questions

  • What is the specific functionality of the pushers integrated into the case band regarding the adjustment of the moon phase versus the calendar functions?
  • Are there any unique features of the Caliber 2601 that differentiate it from base calibers used in vintage Omega Cosmic models?

Source evidence

Recorded claims and source quotations for Omega Cosmic Collector's Series Number Two
FieldSource-reported valueSource quotation
ModelCosmic“Omega, 'Cosmic'”
Case Material18K pink gold“18K pink gold wristwatch”
ReferenceBG 156.2001“Ref. BG 156.2001”
MovementCaliber 2601“Cal. 2601”
Dimensions33.5 x 33 mm“Dim. 33.5 x 33 mm”
Jewels31“31 jewels”
Case Serial57977930“case No. 57977930”

Visible details

  • Black dial with pink gold baton, dagger, and pyramidal indexes
  • Pushers integrated into the case band for calendar adjustments
  • 18K pink gold square case with stylized straight lugs
  • Moon phase aperture positioned at 6 o'clock

Research qualifications

  • The auction description recommends an overhaul at the buyer's expense
  • The provided guarantee is noted as void

Photograph identity and source facts were screened before import; rights clearance remains pending.

Consulted source

'1951 Cosmic' Omega, 'Cosmic', No. 768/1951, case No. 57977930, Ref. BG 156.2001. Collector`s Series Number Two from the Museum Collection. Made in 2001. Fine and rare, square, self-winding, water-resistant, 18K pink gold wristwatch with triple date, moon phases and an 18K pink gold Omega buckle. Accompanied by a guarantee (now void) To be sold without reserve

Reviewed 2026-10-26 · Record 882bf1f156

Terms in this record

Glossary explanations for terms named in this object’s record.

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