1978 Rolex Submariner Date MK1 (Ref: 1680) (40mm, Automatic)

The Submariner Date ref. 1680 from 1978 sits at a quiet turning point in Rolex history. It retains the purposeful feel of the early tool watches yet wears the refinements that nudged the Submariner toward everyday use. By this time the red-text dials were gone; a 1978 example will carry the matte “white” MK1 dial with tritium plots, feet-first depth rating (660ft=200m), and the discreet “SWISS – T < 25” line at six. The look is restrained and legible—precisely what collectors value in late-run 1680s.

Under the hood is Rolex’s cal. 1575, the date version of the 1570. In the early 1970s Rolex added hacking seconds to this movement, and by 1978 it was standard—useful for setting time to the second. Power reserve, free-sprung balance with Microstella, and a Breguet overcoil complete a specification built for reliability rather than display.

Two tactile signatures define the reference. First, the acrylic “top-hat” crystal with cyclops magnifier, unique among date Submariners and a key part of the 1680’s silhouette. Second, the bidirectional aluminum bezel insert with period-correct fonts—functional, easy to grip, and prone to the gentle fading that vintage collectors prize.

By the late 1970s, most examples were delivered on the Oyster 93150 bracelet with solid side links and 580 endlinks, replacing the earlier folded 9315. Clasps from this period are date-coded; a 1978 piece typically shows the “VC” stamp. The shift brought a sturdier feel without altering the clean, flat three-link profile.

What remains, then, is balance: a 40 mm steel case with rounded crown guards, a dial that favors function over flourish, and a movement engineered to work quietly for decades. The 1978 1680 MK1 does not shout. It offers a crisp snapshot of the Submariner on the eve of modernity—still acrylic, still matte, yet unmistakably Rolex in its calm, confident execution.