Omega Speedmaster Professional Moonwatch 3590.50.00 – Calibre 861 Tritium 1991 – Box & Papers – Omega Serviced

Info

There are watches that need no introduction, and the Speedmaster Professional 3590.50.00 is certainly one of them. It evokes the space conquest and the heroic spirit of the 1960s, yet it belongs to a different era — one that marks the end of the tritium and Calibre 861 cycle, before the arrival of Super-Luminova and modern production. It’s the last true Moonwatch in its purest form: authentic, mechanical, and timelessly functional.

Produced between the late 1980s and mid-1990s, this reference retains all the classic features of the Speedmaster lineage: the 42 mm asymmetrical case with lyra lugs, the double-engraved NASA caseback, the black tachymeter bezel, and the hesalite crystal that gives off that warm reflection unique to tritium-era pieces. The overall balance is perfect, with a vintage charm that deepens over time thanks to the golden patina of the indexes — one of the most beloved details among collectors.

Inside beats the hand-wound Omega Calibre 861, derived from the Lemania 1873 — a movement designed for endurance, precision, and reliability under any condition. Less complex than the previous 321 but more stable in daily use, it embodies mechanical functionality at its best. It’s the same calibre that powered the Speedmaster during the Apollo missions — the beating heart of a legend.

The 3590.50 is most commonly paired with the 1479 bracelet with 812 end links, occasionally replaced by the rarer 1450 variant. The matte black dial, crisp white inscriptions, and warm creamy tritium markers create a harmonious contrast and a distinctive identity. Each example develops its own character as the tritium ages, making every watch unique in tone and presence.

Owning a 3590.50 means owning a piece of Speedmaster history — a watch that bridges the vintage and modern worlds with perfect balance. It’s pure analog charm, solid tradition, and restrained elegance united in one design. A perfectly wearable vintage Moonwatch that captures the spirit of an era when time itself was something humanity was still learning to conquer.

Case, Bracelet, Dial & Glass

The 42 mm stainless steel case of the Omega Speedmaster Professional Moonwatch ref. 3590.50.00 is in excellent condition, showing only minimal signs of wear invisible to the eye when worn. The black tachymeter bezel — “dot next to 90/70” with TACHYMETRE inscription (without accent) — is perfectly correct and period-appropriate for this reference. It remains clean and well-preserved, displaying only light marks consistent with careful use, while retaining the technical elegance that defines the Moonwatch.

The Omega 1479 stainless steel bracelet with 812 end links, composed of 22 links, completes the watch beautifully. Fully brushed on the top surface, with only the side edges polished as per Omega’s original finish, it has been carefully refreshed while preserving the correct grain and factory orientation. The structure is tight and free from notable wear; the length fits wrists up to approximately 20.5 cm. A slight natural stretch is present, typical of period bracelets, without affecting comfort or appearance.

The matte black dial is perfectly preserved, featuring tritium hands and hour markers that have developed a warm sandy-golden patina consistent with the age of the watch. The white print remains sharp, the logo and minute track perfectly crisp, highlighting the graphic purity that makes the Speedmaster an enduring icon.

The hesalite crystal is clear and free from significant scratches, allowing the dial to be admired in full brilliance while offering the warm, soft reflections typical of pre-Luminova (tritium) Speedmaster models.

Accessories & Warranty

The watch comes complete with its original Omega box, both inner and outer, along with the card holder and the blank warranty card (undated and unstamped), as well as the Omega service card from the authorized service center that performed the overhaul. It is also accompanied by the O&D Vintage certificate of authenticity and lawful provenance.

Produced in 1991 (serial 48.27**)**, the watch has undergone a full overhaul by an authorized Omega service center. The service is covered by an official 24-month Omega warranty, protecting the movement against mechanical defects not caused by improper use or accidental damage. An additional guarantee of peace of mind for the new owner — ensuring a fully serviced and certified timepiece maintained to the highest Omega standards.