Tantalum is named after a punishment, and it is used here for very nearly that reason. F.P. Journe built one Tourbillon Souverain in it, for the Only Watch charity auction of 2015, and there is no second example. The case is tantalum, at 40 mm across and 9.9 mm deep. The dial is chrome blue with whitened guilloche silver, carrying the screwed steel circles the manufacture patented. Inside is the calibre 1403 in 18K rose gold, hand wound, a tourbillon with a constant force device and a dead beat seconds, with the hours and minutes at 3 o'clock, the small seconds at 6 and the power reserve at 12. Twenty turns of the crown give it a reserve of forty-two hours. It sold on the seventh of November 2015 and has not been seen in a catalog since.
Tantalum is a metal almost nobody uses and the reasons are practical rather than aesthetic. It is extremely hard, extremely dense, and close to chemically inert, which sounds ideal for a watch case until you try to machine one. The metal is ductile at the same time as being hard, so it tears rather than cutting cleanly, it destroys tooling at a rate that makes any kind of production planning difficult, and finishing it to a Journe standard means fighting the material through every single operation from start to end. F.P. Journe names the difficulty directly: tantalum takes its name from Tantalus, who in Greek myth stood in water he could not drink beneath fruit he could not reach, and the metal was named for the way it refuses to absorb acid. What you get in return is a color no other watch metal produces. Tantalum reads as a dark blue-gray, noticeably cooler and heavier in tone than either steel or platinum, with a slight blue cast to it that is very hard to photograph properly and quite unmistakable in the hand. On a watch carrying a chrome blue dial, that is plainly not a coincidence. The case and the dial were chosen together rather than one after the other.
The dial is chrome blue over whitened guilloche silver, with steel circles screwed onto its surface, and those circles are a patented piece of F.P. Journe dial construction rather than a decoration. On the standard Tourbillon Souverain they appear as polished steel rings holding the subdial and the aperture in place, visible fixings left deliberately on show in the way the manufacture has always preferred. Against a chrome blue field they do considerably more work than usual, because blue is a saturated color and steel is not, so the rings and their screws become the only neutral elements on the face and they draw the eye directly to the three places something is happening. The blue of the dial itself was clearly chosen to sit against the tantalum around it. Case and dial are both cool and both carry a blue cast, so the watch reads as one single object in a single temperature rather than as a dial mounted inside a frame, which is very nearly the opposite of how most colored dials are handled. The usual approach is to put a strong dial inside a neutral case and let the contrast do the work; here there is no contrast to speak of, and the watch depends instead on the two surfaces agreeing.
Only Watch is a charity auction held every two years to fund research into Duchenne muscular dystrophy, and it works on a very simple principle: manufactures contribute unique pieces, the pieces are sold in a single sale, and the proceeds go to the cause. What makes it unusual as an institution is that it has become the one occasion on which almost every serious watchmaker builds something they would not otherwise build. The one binding constraint is that the piece must genuinely be unique, which rules out putting a special dial on a production run and forces an actual decision to be made. F.P. Journe has contributed to it repeatedly over the years and has generally chosen to change a material rather than a design, which is a harder and considerably less showy route to take than an engraved dial or an unusual color would be. A tantalum case on a tourbillon is exactly that kind of decision: nearly invisible in a photograph, entirely obvious in the hand, and impossible to repeat without going through the whole machining problem a second time. That is a more meaningful contribution to a charity sale than a coat of paint, and it costs the manufacture considerably more to make.
A documented one-off is bought on its record, and this one happens to have an unusually good record behind it. The sale was public, dated and reported, so the auction result, the foundation's documentation and the manufacture's own confirmation should all agree with each other and with the watch in front of you. Establish all three of those before anything else is discussed. On the case, tantalum is hard enough to resist most damage but cannot be refinished in the way a precious metal can, so examine the profile against its original lines and treat softened edges as permanent. Look across the chrome blue dial in daylight from several angles for unevenness, since a colored dial on a unique piece has no reference specification to be restored toward. Confirm the screwed steel circles are seated properly and that none of the fixings has been disturbed. Then wind it fully, twenty turns from empty, and watch the seconds hand step cleanly once a second with no drift. Have the carriage inspected by a specialist, and establish the service history in full, since there is no second example anywhere to compare a repair against.
