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A magnificent Rolex Oyster Perpetual Date Ref. 1501—one of the most compelling and distinctive references within the Oyster family from the mid-1960s.

The 1501 reference belongs to the «Date» line and features a 34 mm diameter—the classic size for that era—which is exceptionally elegant and comfortable on the wrist.

Key features that define this 1966 timepiece include:
The iconic «Engine-Turned» bezel: This is the most distinctive trait of the 1501 reference.
Crafted from metal (not gold) and featuring geometric notches, it gives the watch a technical, sporty, and remarkably robust appearance.

Automatic Caliber 1570: This movement shares the same high-end mechanical architecture as its larger counterparts from the same period. It is a highly reliable, stable automatic movement, renowned in the world of vintage horology for its legendary durability.

Non-quickset mechanism: Like other movements from that year, it lacks a «quickset» date function; the date is adjusted by advancing the hands past midnight.

Dial with a unique patina: The black dial displays an organic, «tropical» aged patina—highly sought after by collectors. Its granular texture lends it an authentic, one-of-a-kind character, complemented by applied baton-style hour markers and the original «T SWISS T» marking, which confirms the use of tritium during that era.

Water-resistant Oyster case: With its original signed crown and screw-down case back, it offered the signature water resistance that helped propel the brand to fame. That said, I never recommend exposing vintage watches—or even modern ones more than 10 years old (pre-2016)—to water.

Without a doubt, this is a timepiece with a perfectly executed, instrumental aesthetic and exceptional vintage charm.

Case Reference: 1501 (stamped inside the caseback)

Serial Number: 1,303,993 (engraved between the lugs).

Year of Production: Manufactured in 1966 (approx. late 1965 to early 1966). The internal caseback bears the date stamp II.65, confirming the case was stamped in the second quarter of 1965 and assembled at the factory shortly thereafter

Caliber: Rolex Caliber 1570 (automatic movement featuring a 360° Perpetual rotor).
Frequency & Architecture: Operates at 19,800 vibrations per hour (vph) with 26 jewels, Microstella regulation screws, and a Breguet overcoil hairspring. It is officially certified as a Chronometer (COSC).

Purple Reversing Wheels: Features the iconic Teflon-coated purple anodized reversing wheels on the automatic winding module (a signature mark of authenticity for the Rolex 15xx caliber family).

Complication: Semi-instantaneous date change at 3 o’clock. (Note: The Caliber 1570 family introduced the hacking/stop-seconds feature later in 1972; thus, this 1966 unit is non-hacking)

Bracelet Reference: Ref. 7205, corresponding to a 19 mm stainless steel riveted Oyster bracelet (Riveted Oyster Bracelet).

Endlinks / End Pieces: Stamped No. 57 (19 mm hollow endlinks designed specifically for 34 mm Oyster cases without crown guards).

Clasp: Folding scissor-style clasp stamped with a 2 over a 66 (marked 2/66), denoting its manufacture in the second quarter of 1966.

The perfect alignment between the caseback (II.65), serial number (1.3M from 1966), and clasp date code (2/66) confirms a completely original and era-correct matching set (matching period)

The original black tritium dial shows a pronounced natural patina/aging (known as a Tropical / Stardust dial).

This speckled effect—caused by the natural degradation of the lacquer layer over 60 years of exposure to UV light and mild ambient humidity—is a highly sought-after phenomenon in vintage watch collecting due to its unique character. It retains its original applied steel baton hour markers and period-correct date wheel.

Case: Stainless steel 34 mm Oyster case with brush-finished lug tops and polished sides. It retains sharp edges and strong lug proportions.
Bezel: Stainless steel engine-turned bezel (a key feature distinguishing Ref. 1501 from the smooth-bezel Ref. 1500).

Crystal: Acrylic plexiglass crystal featuring the iconic Cyclops magnifying lens over the date aperture at 3 o’clock.

Mechanical Condition: Having undergone a full movement service just one year ago, the
Caliber 1570 operates in optimal condition—properly lubricated, cleaned, and adjusted—providing exceptional operational reliability for a nearly six-decade-old timepiece