Among all the stone dials Rolex has ever produced, few have captured the imagination of collectors the way the "Obsidian" Datejust has in recent years. It has quietly risen to the level of a grail: a dial that rarely, if ever, surfaces in public, that changes hands almost entirely behind closed doors, and that survives in numbers so small most collectors will never encounter one in the metal. And yet, for all its allure, the story behind these dials is far from settled. What the stone actually is, why the pattern looks the way it does, whether the name is even correct: none of this has been fully answered. Having had one in our hands, we would like to lay out what is known, what is suspected, and what remains open.
Begin with the dial itself, because that is where the fascination starts. Black and brown do not sit side by side here so much as flow into one another, and the result is a figure that is dynamic, almost dreamlike, and never the same twice: no two Obsidian Dials share a pattern. Hold one at a distance and the shapes start to resemble continents drifting across a dark sea, like the world map printed on the dial of a world-time watch.
So where does this landscape come from? The conventional explanation begins with how Rolex builds a stone dial: a thin slice of stone is bonded onto a brass base. Obsidian, the stone this dial takes its name from, is a black, glass-like volcanic rock, and being glass-like it is not entirely opaque. The theory, then, goes that what we are looking at is the brass base showing through the translucent stone, and that it is this glimpse of metal beneath the surface that produces the pattern. It is a tidy account, and for years it has been the accepted one. The trouble is that it does not survive close inspection.
The name itself is the first clue. "Obsidian" only came into common use among collectors within the past few years; it is a label the market gave the dial, not one Rolex did, and there is no evidence that an obsidian dial ever appeared in the catalogue at the time. The pattern raises further doubts. If brass were simply showing through a slice of stone, one would expect the figure to be scattered at random, yet on almost every Obsidian Dial it gathers around the hands and follows the edges: the outer perimeter, the frame of the date window. The pattern appears, in other words, exactly where the stone has been cut, drilled, or pressed against something. The texture is also far smoother than natural obsidian would allow, and the overall look bears little resemblance to the obsidian dials found on later five-digit references. Taken together, these observations point toward a different picture. It has been suggested that these are in fact onyx dials, and that the figure is not a feature of the stone at all but the trace of a reaction between the stone and its metal base, developing slowly over decades. The idea finds support outside Rolex: a Patek Philippe dial of the very same appearance has been recorded, and its Extract from the Archives lists the material simply as "onyx."
Whatever the stone turns out to be, one thing does not change: this is among the rarest configurations of any Rolex stone dial. If the reaction theory is right, then what we are looking at is a stone dial that has aged the way a tropical dial does, its surface rewritten by time, and "tropical onyx" may be the more honest name. Which brings us to authenticity, an unavoidable question with any dial this sought after. The text at six o'clock on natural-stone dials comes in three variants, T SWISS T, SWISS, and SWISS MADE. Among the popular onyx dials, SWISS MADE examples are unusually common, common enough that it is hard to believe all of them are genuine. This example reads T SWISS T. As for how many exist, the honest answer is that no one knows; what can be said is that publicly recorded sales over the past few years amount to only a dozen or so pieces worldwide. For decades these dials sat unnoticed, and it took the recent revival of the dress watch to bring them into the light. The Obsidian Dial is, in that sense, a grail of a new era: one that was there all along, waiting to be seen.