2F70-5380, BLUE AGATE AND ONYX TANK

A Seiko Credor, ref. 2F70-5380, in stainless steel at 25.5mm by 30mm. The tank-shaped case frames a dial cut from blue agate stone and set with black onyx, so every example carries its own pattern, touched with fine gold markers. Inside, the ultra-thin 2F70 quartz movement lets the whole watch lie almost flat. It is worn on a steel mesh bracelet that moves like fabric, and it still carries its original caseback sticker.

Credor began in 1974 as Seiko's highest line, its name taken from the French crête d'or, crest of gold. Through the 1970s and 1980s Seiko used Credor to show what Japanese watchmaking could do at the very top, and thinness was one of its great obsessions. The 2F70 quartz calibre was made for exactly that, allowing slim, elegant cases like this one.

We sourced it for the dial. The blue and black layers change with every angle, moving from almost black to a bright ocean blue as the light finds them. The mesh bracelet is woven so finely that it drapes rather than links, and the whole watch feels light and liquid on the wrist. The original caseback sticker is still in place, a small time capsule from the decade it was made. It is a side of Seiko many collectors never get to see. Curated with intent.