The Omiwatari. Lake ice, hand-wound Spring Drive, 10.2mm.

Spring Drive is Grand Seiko’s own idea: a mainspring drives the watch like any mechanical movement, but instead of an escapement the speed is governed by a tiny electromagnetic brake regulated by a quartz reference, so the seconds hand sweeps without any tick and the rate holds to about a second a day. The 9R31 is the hand-wound version, which lets the case be 10.2mm thin and puts the power reserve indicator on the back where it does not clutter the dial. The dial is the point: Omiwatari is the pressure ridge of ice that appears across Lake Suwa, near the Shinshu studio where the watch is made, and the texture and colour are taken from it.

At 38.5mm with a 43.7mm lug to lug it wears like a dress watch from the 1960s, and the crocodile strap is what it is meant to be worn on.

The listing carries the reference SBGY007 in the title and model row and calls it the Lake Suwa Omiwatari Elegance with a calibre 9R31, 38.5mm, 10.2mm, a dual-curved sapphire and a leather band; its 100-metre and gold-band rows are wrong for the reference. The photograph shows the ice-texture dial, blued seconds hand and black crocodile strap. The lug to lug, movement type, reserve, accuracy, splash resistance, clasp and list price are Grand Seiko’s published figures.

The dealer is Luxor Watches, a marketplace dealer, and the rows we read do not state whether the watch is new with Grand Seiko’s warranty card; ask, and ask for the box and the card. Nothing here was measured on the watch.

This is a regular Amazon listing from a marketplace seller with Amazon’s 30-day return window; it is not a Luxury Stores pre-owned unit and the seller has not published a condition. The second button opens the live search for Grand Seiko Spring Drives in case this one has sold.

Grand Seikos have resold for under new and close to what pre-owned buyers paid, sometimes more, sometimes less; that is a pattern, not a promise, and nothing here is investment advice.