Monochrome Watches
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Grand Seiko Celebrates The 25th Anniversary of Calibre 9S With The SBGH311 and SBGR325

Two limited editions with nature-inspired dials and variations of Grand Seiko’s breakthrough automatic calibre 9S celebrate an important quarter-of-a-century milestone.

| By Rebecca Doulton | 4 min read |
Grand Seiko SBGH311 and SBGR325

Grand Seiko celebrates the 25th anniversary of its breakthrough calibre 9S with two special models from its Heritage collection and dials inspired by the changing skies over Mount Iwate. In honour of the first GS watch fitted with the in-house 9S movement – created by Grand Seiko’s head of design Nobuhiro Kosugi in 1998 – the anniversary models share the same case design and compact 37mm diameter. Straightforward three-hand-and-date models, one is fitted with Hi-Beat calibre 9S85 and the other with the three-day automatic calibre 9S65; both are limited editions of 1,200 pieces.

The Calibre 9S – recap

Grand Seiko never does things by half measures. When it started life in 1960, the collective goal was to build the “world’s best watch”, incarnated by the Grand Seiko Chronometer. Seven years after its birth, the Grand Seiko style was consolidated in the 44GS model. Nine specific design elements were established with the 44GS that are still seen in today’s models, including the use of reflections or “sparkle of quality” in the form of faceted hands and markers designed to reflect even the smallest ray of light.

Another milestone in the Japanese brand’s development occurred in 1998 with the introduction of calibre 9S, a precision in-house automatic movement designed from scratch that would become the new Grand Seiko Standard for mechanical watches. Its superior levels of performance surpassed watch industry standards, and the 9S has become the cornerstone of all mechanical watches in the GS family (not Spring Drive).

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Using the 9S as a foundation, a host of new movements have emerged over the years, including the Hi-Beat 9S85 in 2009, the 9S65 three-day power reserve in 2010 and the 9S86 with Hi-Beat and GMT function in 2014. Coinciding with the brand’s 60th anniversary, calibre 9SA5 was released in 2020, the most advanced Hi-Beat Grand Seiko movement to date. All 9S mechanical movements are crafted in the Grand Seiko Shizukuishi Studio, located in an area renowned for its breathtaking landscape dominated by the snow-capped peak of Mount Iwate.

The core collections of Grand Seiko – HeritageElegance and Sport – are all fitted with superlative movements and finished with traditional Japanese attention to detail and time-honed artisanal crafts. As its name indicates, the Heritage line pays tribute to the early Grand Seikos, and many models have dials with colours or motifs directly inspired by nature.

The Grand Seiko SBGH311

The Grand Seiko Heritage Collection Calibre 9S 25th Anniversary Limited Edition SBGH311 (official name) is the brand’s first global release that unites a Hi-Beat movement with the original 37mm case size designed by Nobuhiro Kosugi in 1998.

Grand Seiko SBGH311 and SBGR325
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As our readers know, Grand Seiko is gaining a cult following for its in-house textured dials that capture some of Mother Nature’s most beautiful scenes, like the coveted White Birch or the delicate pink sakura-inspired dial of the 44GS.

This anniversary edition with a silvery-white dial recreates the sea of clouds that blanket Mount Iwate at daybreak. To create the mottled dial pattern, GS artisans used electroforming. The central seconds hand is tempered in blue, and the Grand Seiko logo is applied in a gold colour to commemorate the 25th anniversary of the 9S movement.

Grand Seiko SBGH311 and SBGR325

In honour of the first GS watch fitted with the breakthrough 9S movement – SBGR001 – the dimensions are identical to the original with a 37mm diameter and a thickness of 13.3mm. The hand-assembled movement powering this model is the Hi-Beat 36000 automatic mechanical calibre 9S85 with an accuracy rate of +5/-3 seconds a day and a power reserve of 55 hours. The titanium openworked oscillating weight reveals a mottled blue colour achieved with an anodic oxidation process.

Limited to 1,200 pieces, the SBGH311 will be available exclusively from Grand Seiko’s Online Boutique in January and from February 2023 at Grand Seiko Boutiques and select retail partners worldwide.

Quick facts: SBGH311 – 37mm diameter x 13.3mm thickness x 46.6mm lug to lug – stainless steel – 100m water-resistant – Hi-Beat automatic calibre 9S85 – 36,000vph/5Hz – 37 jewels – 55h power reserve – +5/-3 seconds a day – limited edition 1,200 pieces – EUR 7,200

The grand Seiko SBGR325

The Grand Seiko Heritage Collection Calibre 9S 25th Anniversary Limited Edition SBGR325 (!) is the second commemorative model and celebrates the clear blue skies of the Iwate Prefecture, where Grand Seiko mechanical watches are made. A silky smooth sunray finish on the pale blue dial reflects light from every angle and the sharp diamond-cut hour and minute hands alight on the applied, faceted and polished indices. The stainless steel case size is identical to the Hi-Beat model, revealing the superlative hand finishings and bright polished accents extending to the bracelet and triple-folding clasp.

Grand Seiko SBGH311 and SBGR325
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Powered with Grand Seiko’s three-day automatic movement – calibre 9S65 – the openworked rotor is also blue and can be seen through the see-through caseback.

Limited to 1,200 pieces, the SBGR325 will be available at Grand Seiko Boutiques and retail partners worldwide in April 2023.

Grand Seiko SBGH311 and SBGR325

Quick facts: SBGR325 – 37mm diameter x 13.3mm thickness x 46.6mm lug to lug – stainless steel – 100m water-resistant – automatic calibre 9S65 – 28,800vph – 35 jewels – 72h power reserve – +5/-3 seconds a day – limited edition 1,200 pieces – EUR 5,800

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