Rolex GMT-Master 1675

The Rolex GMT-Master 1675 enjoyed an exceptionally long production run, spanning from 1959 to 1980. As the successor to the original Ref. 6542, the 1675 introduced several key features that defined the model for decades, most notably protective crown guards and a larger 40mm case. It replaced the fragile Bakelite bezel of its predecessor with a more durable anodized aluminum insert, famously offered in the iconic blue and red “Pepsi” colorway, alongside all-black and, for precious metal versions, brown “Root Beer” options. The watch retained the signature fourth GMT hand and rotating 24-hour bezel, allowing tracking of a second time zone, a feature initially developed for Pan Am pilots. Powered initially by the Caliber 1565 and later the higher-beat Caliber 1575 (which gained hacking seconds around 1971), the 1675 never featured a quickset date function. Its significance lies in its longevity, its role in popularizing the GMT function for travelers, and its evolution through key vintage Rolex eras, including the transition from gilt dials (~1959-1967) to matte dials (~1967-1980), making it a cornerstone reference for collectors.  

Specifications

(Note: Dimensions like diameter and thickness can show minor variations across sources and production years.)

Variations and Key Features

The Rolex GMT-Master Ref. 1675’s long production run resulted in numerous variations, particularly in the case, dial, and bezel. These details are crucial for dating and valuing specific examples.

Case:

• Crown Guards: A defining feature introduced with the 1675.
  • Pointed Crown Guards (PCG / “Cornino”): Found on early models (~1959 – ~1963/64). Variations exist within PCGs (early flat-top vs. later broader points).  
  • Rounded Crown Guards (RCG): Transitioned around 1964/65 and used for the remainder of production, with subtle evolution towards smoother profiles.  
• Thickness: Early cases (~pre-1967) are sometimes referred to as “thin cases” (~12.7mm) compared to later standard cases (~13.0mm).  
• Materials: Offered in Stainless Steel (1675), 18k Yellow Gold (1675/8), and Steel/14k Yellow Gold Two-Tone (1675/3).  
• Case Maker: Includes Genex (Poinçon de Maître key #12).  
• Crown: 5.3mm Twinlock screw-down crown.  

Movement:

• Caliber 1565: Used from ~1959 to ~1965. 18,000 VPH beat rate.  
• Caliber 1575: Used from ~1965 to 1980. Higher beat rate (19,600 VPH). Gained hacking seconds function around 1971.  
• Common Feature: Both calibers lacked a quickset date function.  

Dial:

• Gilt Dials (~1959 – ~1967): Glossy black surface with gold-colored text/tracks.
  • Chapter Ring: Early versions featured a closed minute track circle. Transitioned to open track ~1963.  
  • Lume Indicators: “Exclamation Point” (~1962) and “Underline” (~1963-64) signified transitions in luminous material (Radium to Tritium).  
• Matte Dials (~1967 – 1980): Flat black surface with white printed text. Numerous variations exist, often categorized by “Marks”:
  • Mk 1 “Long E”: Distinctive ‘E’ in ROLEX, thin coronet (~1967-72).  
  • Mk 2: Stout coronet, close ‘LE’ spacing (~1972-75).  
  • Mk 3 “Radial”: Small, centrally positioned lume plots (~1975-78).  
  • Mk 4: “Standard” layout for the mid-1970s.
  • Mk 5: Specific text alignment (M over C), taller coronet (~1977-79).  
  • Mk 6: Final dial type (~1979-80).
• Nipple Dials: Exclusive to gold (1675/8) and two-tone (1675/3) models. Applied conical gold markers. Available in black or brown (matte, glossy, or sunburst).  
• Tropical Dials: Gilt or matte dials aged to brown hues.  
• Co-Branded/Insignia Dials: Rare dials featuring retailer names (Tiffany & Co.) or state/corporate logos (UAE Eagle, Omani Khanjar, AB).  

Hands:

• Standard Mercedes hour hand, pencil minute hand.  
• GMT Hand: Early versions (gilt era) had a small triangle; later versions (matte era, from ~1967) had a larger triangle.  

Bezel:

• Material: Anodized aluminum insert. Bidirectional friction bezel.  
• Pepsi (Blue/Red): Available throughout production for steel models. Known for “Fat Font” variations on early inserts and various fading patterns (Pink, Ghost, Fuchsia). Original inserts have a red back.  
• All-Black: Alternative for steel, also used on gold/TT models. Introduced ~late 1960s/early 1970s. Original inserts have a black back.  
• Root Beer (Brown/Gold or All Brown): Exclusive to gold (1675/8) and two-tone (1675/3) models.  
• Blueberry (All Blue): Extremely rare; status as a standard factory option is debated.  

Bracelet:

• Offered on both Oyster (e.g., Ref. 7836 folded, 78360 solid) and Jubilee (e.g., Ref. 6251H folded, 62510 solid) bracelets.  
• USA-made bracelets (e.g., oval-link Jubilee) were common for the US market.  
• Correct end links (e.g., 580 for Oyster) and clasp date codes are important for originality.  

Additional Information

The Rolex GMT-Master Ref. 1675 is a cornerstone of vintage Rolex collecting, highly valued for its historical significance, iconic design, and the sheer variety of configurations produced over its 21-year lifespan. Its connection to the golden age of aviation and Pan Am gives it a unique narrative appeal.  

Collectibility is heavily influenced by originality and condition. Unpolished cases, original dials with matching hand/lume patina, and period-correct bezel inserts are paramount. Rarity drives value, with early Pointed Crown Guard models, gilt dials (especially chapter ring, Exclamation Point, or Underline variants), specific matte dial Marks (like the Mk 3 Radial), and desirable bezel fades (like Fuchsia) commanding significant premiums. Co-branded or insignia dials represent a top tier of rarity.  

The 1675 serves as a crucial transitional reference, showcasing Rolex’s evolution from the 1950s tool watch aesthetic towards more modern designs, including the shift from radium to tritium lume and from gilt to matte dial production techniques. Its enduring design and robust mechanics make it not only a collector’s item but also a wearable piece of horological history. Due to the complexity and value associated with this reference, prospective buyers should conduct thorough research and seek expert advice to verify authenticity and condition.