Seiko - Grand Seiko - No reserve price - 5646-7000 - Men - 1970

Offered in this auction by Second Vintage This represents a quintessential example of Japanese horological history, a Grand Seiko 56GS from the golden era of the Suwa Seikosha factory. Known for adhering to the "Grammar of Design" with its sharp case lines and superior finishing, this reference 5646-7000 features the highly desirable Hi-Beat automatic movement. A standout feature of this specific example is the preservation of the iconic gold GS medallion on the caseback, a detail often lost to time and wear. Brand: Seiko Model: Grand Seiko Reference Number: 5646-7000 Serial Number: 0D1010 Movement: Automatic Caliber 5646A Dial: Silver Sunburst Case Size: 36 mm (excluding the crown) Case Material: Stainless Steel Production Year: 1970 Condition: Excellent vintage condition. The watch is remarkably preserved with defined case geometry and a flawless gold medallion, and timegrapher results showing -10 to -12 seconds per day indicate a healthy movement with strong amplitude. Dial and Hands The silver sunburst dial is in beautiful condition, radiating a clean metallic sheen that captures the light elegantly. There is some small wear visible in the outer edges of the dial. It features sharp, applied baton indices with black inlays that match the dauphine hands, ensuring excellent legibility. The applied Seiko logo at the top is balanced by the gold-tone applied "GS" logo above the six o'clock position, accompanied by the Hi-Beat text and the Suwa factory whirlpool symbol. A framed day-date window is positioned at three o'clock, with the text remaining crisp and clear. Case and Crystal The stainless steel case follows the classic 7000-series cushion design, characterized by broad, sweeping surfaces and short lugs that hug the wrist. The case retains its architectural integrity with visible original brushing and sharp lines, showing only light surface scratches consistent with careful usage. The crown is original and signed with the GS logo. The screw-down caseback is a highlight, featuring the textured gold Grand Seiko medallion which is fully intact and in pristine condition, a rare find for this reference. The crystal is clear and free of distracting marks. Movement Powering this timepiece is the high-grade Seiko Caliber 5646A, an automatic movement featuring 25 jewels and operating at a Hi-Beat frequency. The movement presents cleanly in the photos and offers reliable vintage performance. Timegrapher testing indicates the watch is running between -10 and -12 seconds per day with strong amplitude, suggesting the mechanism is mechanically sound and functioning well within vintage tolerances. Strap The watch is fitted with a high-quality black textured leather strap featuring contrasting white stitching. The strap is in new condition and complements the monochrome aesthetic of the dial and case, offering a sporty yet sophisticated look suitable for daily wear. Condition This piece is in excellent vintage condition. The dial is free from spotting or moisture damage aside from the mentioned small wear on the outer edges, and the hands show no corrosion. The case metal is honest and unpolished, preserving the original factory geometry. The gold medallion on the caseback is the crowning feature of this specific watch's condition, as these are frequently worn smooth or missing entirely on similar vintage models. Dimensions The case measures 36 mm in diameter excluding the crown, a classic proportion that wears slightly larger due to the cushion case shape. Remarks The 56GS series is widely regarded as one of the most practical and wearable vintage Grand Seiko lines. This Reference 5646-7000 combines the practicality of an automatic day-date movement with the high-end finishing standards that defined Grand Seiko's resurgence in the late 1960s and early 1970s. It is a collector-grade piece that offers both historical significance and everyday usability. History Produced in December 1970, this watch hails from a pivotal time when Seiko was competing directly with, and often beating, Swiss chronometers in accuracy trials. The 56GS was one of the last great mechanical series produced before the Quartz Crisis fully took hold, making it a significant artifact of the peak mechanical era of Japanese watchmaking. The presence of the Suwa Seikosha logo indicates its manufacture at one of Seiko's two prestigious rival factories, renowned for producing high-end innovative movements. / Second Vintage SKU: SEI-SGH-0002