Setting a Celestial with rubies is a decision that works against the dial rather than with it, and that is the point of the reference. The watch carries a rotating sky chart in blue, showing the night sky as seen from a fixed latitude with the visible portion marked by an ellipse, a meridian line, the angular motion of the Moon and the meridian passage of Sirius. Ringing that cold blue display with red stone produces a hard contrast at the edge of the dial and changes what the watch is doing on the wrist, turning a contemplative instrument into something that announces itself. The alternative version of the same reference uses sapphires and does the opposite. The case is platinum at 44 mm and the watch runs to 2028. Both versions have been catalogued since 2014 without redesign, which is unusually long for a jewelled reference and indicates the pair was conceived together rather than one being added later as a variation on the other.
The case measures 44 mm across and 11.33 mm thick, dimensions set by the display rather than by the movement, since a sky chart has to carry a legible hemisphere and there is a size below which the constellations stop resolving. The bezel is set with baguette rubies. Ruby is harder than emerald and takes the tension of a setting more readily, which matters on a bezel of this diameter where each stone has to be individually cut to the curve, and the colour holds its saturation against a dark dial in a way softer stones do not. Platinum beneath the setting keeps the case cold and prevents the red from picking up warmth from the metal, which would happen immediately on a gold case and would pull the whole watch towards a different register. The case back is sapphire crystal, the hands are white gold and skeletonized so that the chart remains visible when they pass over it, and the strap is alligator. The setting also has to survive a case of this diameter without any stone sitting proud of the profile. A 44 mm bezel is a long run for baguettes, and the number of individually cut stones required to follow that curve without a visible break in the line is considerably higher than on the smaller cases elsewhere in the collection.
The mechanism drives two sapphire discs above the dial at different rates, one carrying the star chart and one the Moon, both running on sidereal time rather than the solar day so that the chart stays aligned with the real sky rather than drifting across the year. Mean solar hours and minutes are displayed conventionally, the date is shown by a peripheral hand, and moon phases derive from the same gearing that moves the Moon across the chart rather than from a separate train. That single point of derivation is the mechanical elegance of the reference, since three indications that would ordinarily require three independent arrangements are taken from one. The complication offers nothing to correct beyond the date and the time, and nothing to operate at all, which means the wearer interacts with the most conceptually ambitious display in the collection almost not at all. Sidereal time is what keeps the chart honest. A sidereal day is about four minutes shorter than a solar one, an error that accumulates to a full day across a year, so a chart driven from ordinary timekeeping would be visibly wrong within a month. The Celestial runs its chart on its own rate for exactly that reason. It is also why the display cannot be corrected against a reference the way a calendar can, since there is nothing to set it to except the sky itself.
The two Celestial references in the current selection are held identical in every respect except the stone on the bezel, this one in ruby and the 6104/11P-010 in sapphire. Patek Philippe has used the same structure elsewhere in the collection, offering one design in several coloured stones so that the choice is about temperature rather than specification, and the Celestial pair is the only instance of it among the grand complications. Both entered the catalogue in 2014 and both leave in 2028, which is the longest window of any reference in the group and unusual for jewelled versions, which more often exit ahead of their plain counterparts. Elsewhere in the group sit two repeaters with perpetual calendars, two repeaters without, and a perpetual calendar chronograph. The Celestial pair is also the only instance in the group where two references share a movement and a case and differ solely in the stone, a structure used more often in the sports and Rare Handcrafts parts of the collection.
This reference suits the collector who wants the Celestial without the reticence that normally comes with it. The complication is inherently introspective, and pairing it with red stone is a way of owning it without the watch reading as a private object, which is a genuine position rather than a contradiction. Buyers who choose the ruby over the sapphire are generally clear about that from the outset rather than arriving at it by comparison. The two versions are also close enough that the decision has to be made in person, since photographs exaggerate the contrast on the ruby and flatten it on the sapphire, and the difference in hand is smaller than images suggest. At 44 mm the reference is large and there is no alternative size. It leaves the catalogue in 2028. The weight of a 44 mm platinum case with a set bezel is also a real consideration, and it is the factor that most often decides the question before the stones do. Anyone drawn to the complication should try both versions on rather than choosing from images, since the case is the constraint here and the bezel is the preference.
