Limited to 100 pieces and sold exclusively through Lange boutiques, the 1815 Rattrapante Perpetual Calendar 421.056FE was presented in 2023 to mark ten years since A. Lange & Söhne introduced the model. Its defining feature is its dial, made of solid Rose Gold and set inside a White Gold case, a contrast of warm and cool metals that gives the anniversary edition a character quite distinct from the Platinum and Rose Gold versions of 2013, both of which carry Silver dials. The watch keeps the combination that made the model a landmark: a split-seconds chronograph able to time two events that start together, and a perpetual calendar that follows the lengths of the months and the leap-year cycle through to 1 March 2100. When it was first launched, the model earned two prizes at the Grand Prix d'Horlogerie de Genève, and the anniversary edition celebrates that achievement with a dial whose colour recalls the salmon and copper tones prized on complicated watches of the mid-twentieth century. It is at once a tribute to the model's first decade and one of the rarest versions of the grand complication at the heart of the 1815 family, made in a quantity that ensures it will remain seldom seen.
At 41.9 by 14.7 mm, the White Gold case shares its dimensions with the earlier versions, with the polished and satin-finished surfaces and notched lugs typical of the 1815 family, and a deployant buckle in White Gold secures the brown alligator strap. The dial is solid Rose Gold with a matte finish, and it is built in layers that give the displays real depth. The main surface carries the railway-track minute scale, subdivided for fractions of a second, and printed Arabic numerals; the subdials at 3, 9 and 12 o'clock form a lower tier, and within them the indications for leap year and remaining running time, together with the moon phase at 6 o'clock, sit lower still. Each subdial pairs two functions. On the left, the date and day of the week; on the right, the month and leap year; at the bottom, the running seconds with the moon phase; at the top, the 30-minute chronograph counter with the AUF/AB indicator. The red numeral 1 on the date scale separates the first of the month from the last. Blued steel hands for the minute counter and the rattrapante stand out against the warm gold, and the moon phase adds a disc of deep blue to the composition. The overall effect is richer and more intimate than on the Silver-dialled versions.
Mechanically, the anniversary edition is identical to the original models, driven by the hand-wound movement Lange developed for the 1815 Rattrapante Perpetual Calendar. Its 631 parts include 211 for the perpetual calendar and 206 for the split-seconds chronograph, which is governed by two column wheels. The chronograph is started and stopped with the pusher at 2 o'clock and reset with the pusher at 4 o'clock; the pusher at 10 o'clock operates the rattrapante, stopping one of the two central seconds hands to record an intermediate time and releasing it to catch up with the other. The perpetual calendar changes the date, day and month at midnight and takes account of leap years automatically, so the owner need only keep the watch wound. With a full wind, the movement runs for 42 hours, and the AUF/AB indicator at 12 o'clock shows when winding is due. A stop-seconds device allows the watch to be set to the second. The plates and bridges are untreated German silver, the balance cock is engraved by hand, and the entire construction can be studied through the sapphire caseback, where the two column wheels and the levers of the rattrapante are clearly visible at work.
A. Lange & Söhne introduced the 1815 Rattrapante Perpetual Calendar at SIHH 2013, in Platinum and in Rose Gold, as its eighth chronograph movement and the first to unite a split-seconds chronograph with a perpetual calendar in the 1815 family. It built on earlier achievements, notably the Double Split of 2004 and the Datograph Perpetual of 2006, and it quickly became one of the manufacture's reference grand complications, recognised with the Grande Complication prize and the Public Prize in Geneva in its launch year. For the tenth anniversary in 2023, Lange chose not to change the movement or the layout but to reinterpret the dial, using solid gold on this model for the first time and pairing it with a White Gold case. Precious-metal dials in warm tones have a long history in complicated watchmaking, and the choice links the anniversary edition to that tradition while keeping it unmistakably Lange. Among the three current versions of the model, the 421.056FE is the only limited edition and the only one with a gold dial, which gives it a clear identity within the family.
The 421.056FE appeals to collectors who want the full technical depth of the 1815 Rattrapante Perpetual Calendar in its rarest and most distinctive form. With only 100 pieces made and distribution limited to Lange boutiques, it is considerably scarcer than the regular versions, and its Rose Gold dial in a White Gold case gives it an appearance that stands apart even among Lange's complicated watches. It will interest collectors who appreciate anniversary editions that alter the character of a model without changing its substance, and those drawn to the warmth of gold dials, which hold a special place in the history of complicated watches. As a combination of split-seconds chronograph and perpetual calendar, it offers daily usefulness and considerable mechanical interest; as a limited edition, it marks a specific moment in the history of the 1815 family. For collectors assembling a Lange collection of lasting significance, it is a reference that combines rarity, recognition and a genuinely distinctive design.
