esigned entirely from scratch, Caliber 9S, which debuted in 1998, represented Grand Seiko’s never-ending pursuit of high accuracy and marked the beginning of a new age for the brand’s mechanical watchmaking. In the same year, the Grand Seiko Standard was re-defined, raising the bar for the brand’s watchmakers and setting a new level of performance that exceeded that of the watch industry’s most respected standard.

Over the past 25 years, the original Caliber 9S has been developed into a full series of movements with different functions, and this series has been enriched with new alloys for both the main and balance springs and MEMS engineering, which allows key components to be manufactured to a tolerance of one-thousandth of a millimeter. Caliber 9S became the platform on which Grand Seiko mechanical movements are built, and this led to the creation of the revolutionary Caliber 9SA5 in 2020.

Today, the 25th anniversary of the first Caliber 9S is celebrated with the birth of two very special Grand Seiko creations, each of which has the same case design and diameter as the first watch that housed the 9S movement in 1998.

Created by Grand Seiko lead designer Nobuhiro Kosugi and his team, the 1998 watch echoed outwardly the uniqueness, the precision, and the beauty of the new automatic movement inside. And yet there was a clear connection to the qualities that had underpinned Grand Seiko watch- making from its earliest days. Impressive yet understated, Kosugi’s watch was suited to everyday wear even as its case and dial played with light. This melding of beauty and understatement, of excellence without pretension, dovetailed with Grand Seiko’s long-held aspiration to be the best possible practical watch. Twenty-five years on, this emblematic case design continues to inspire Grand Seiko, much as the 9S movement inside it.

The SBGH311, inspired by Mt. Iwate’s sea of clouds

One of the commemorative watches is graced by a silver dial whose texture and color evoke the sight of the sea of clouds that cover Mt. Iwate in Iwate Prefecture, where all Grand Seiko mechan- ical watches are manufactured. This scene is only visible at daybreak, when the air is so still and humid that dense clouds overlap to create a beautiful silvery-white sea.

Through the clear sapphire crystal case back, the Grand Seiko emblem is easily visible, set into the titanium oscillating weight whose color was created especially for this watch to suggest the deep-blue sky above the sea of clouds that so often surround Mt. Iwate’s peak. This color is made possible by an anodic oxidation process.

This new creation is equipped with the Hi-Beat 36000 automatic mechanical Caliber 9S85, which is hand assembled by the skilled craftsmen and women of the Grand Seiko Studio Shizukuishi. It has an accuracy rate of +5 -3 seconds per day and delivers a power reserve of 55 hours. A limited edition of 1,200, this watch will initially be exclusive to Grand Seiko Boutique Online, starting in January 2023, and then will be available at the Grand Seiko Boutiques and select retail partners worldwide in February 2023.

The SBGR325, expressing the beauty of the clear skies of Iwate

The second timepiece features a blue dial, expressing the clear and broad sky seen from the top of Mt. Iwate, transporting wearers to Iwate Prefecture, the home of Grand Seiko mechanical watch- making. Its striking sunray finish reflects light from every angle, creating a stunning azure backdrop for the diamond-cut hour and minute hands and indexes. Just like the watch with the silver-colored dial, the seconds hand is tempered in blue and the dial features the Grand Seiko logo in a gold color commemorating the 9S movement.

The signature Grand Seiko blue color is realized on the oscillating weight by the same anodic oxidation process and can be enjoyed through the sapphire crystal case back.

The watch is powered by Caliber 9S65, which has a mean daily rate of +5 -3 seconds per day and a 3-day power reserve. It will be available as a limited edition of 1,200 at the Grand Seiko Boutiques and select retail partners worldwide in April 2023.