Panerai Heralds 90 Years of the Radiomir with Perpetual Calendar GMT Goldtech

In 2025, Panerai will mark 90 years since the debut of its very first wristwatch, the original Radiomir, custom-built for Italian navy frogmen and taking its name from the radium-based luminous paint that made its dial glow brightly underwater. The Radiomir, today recognizable by its big, cushion-shaped case, thin “wire” lugs, conical crown, and two-layered “sandwich” dial, is indisputably worthy of celebration as the wellspring from which the entire modern Panerai collection sprang, and the Florentine-founded, Swiss-based watchmaker is getting a jump on the anniversary festivities with the release of the Radiomir Perpetual Calendar GMT Goldtech — which brings both the firm’s proprietary Goldtech alloy and its recently developed Caliber P.4100 to the OG Panerai product family.

First introduced in a Luminor case (that’s the successor to the Radiomir, which adds the patented, crown-protecting bridge to the emblematic cushion shape) in 2022, the self-winding Caliber P.4100 was the result of more than five years of R&D at Panerai’s Laboratorio di Idee inside its manufacturing facility in Neuchâtel, Switzerland. Packing a three-day power reserve, the movement is noteworthy for incorporating both a perpetual calendar and a dual-time/GMT indicator in addition to the timekeeping — and for displaying all these functions in a stripped-down, ultra-legible arrangement that is true to Panerai’s utilitarian, military origins. With all that’s going on inside, in fact, the sun-brushed ivory dial of the Radiomir Perpetual Calendar could be considered downright minimalist: the hour and minute on central hands, and an additional triangle-tipped GMT hand in the center; day and date in a double window at 3 o’clock, and a subdial at 9 o’clock that combines the running seconds and an “AM/PM” indication. Balancing out the classical “RADIOMIR” and “PANERAI” text below 12 o’clock is the “CALENDARIO PERPETUO” above 6 o’clock, the Italian-language acknowledgment of the timepiece’s inner complexity.

To read the month, year, and leap-year status — arguably, the least urgent bits of information when consulting a calendar — you’ll need to turn the watch over for a back view, through a sapphire window, of Caliber P.4100, into which the indicators for these units of information have been cleverly incorporated, along with an analog display for the remaining power reserve. The movement is decidedly thin for all its complexities — just 7mm high — and uses an off-centered micro-rotor to wind the mainspring, whose 72 hours of running autonomy is stored in two barrels. A brisk balance frequency of 28,800 vph (4 Hz), a KIF shock absorber, and a stop-seconds balance wheel helps ensure reliable timekeeping and easy resetting. Also on the subject of resetting, a clever mechanism devised specifically for this movement enables all changes to the calendar functions to be made easily using just the crown. 

The 45mm, 100-meter water-resistant case — in the classical cushion shape of the earliest Radiomir cases, which were once supplied by Rolex — is constructed from Goldtech, a material developed by Panerai whose composition includes a mixture of platinum and copper and which boasts a rich, reddish hue and a higher level of durability than traditional gold alloys. The “wire-loop” lugs, which evoke the makeshift, soldered style of early pocket watches modified for use as wristwatches, connect the case to a brown alligator strap with tone-on-tone stitching and the familiar trapezoidal Panerai clasp made of the same Goldtech as the case. Available at Panerai retailers as of October 24, 2024, the Radiomir Perpetual Calendar GMT Goldtech is priced at $46,200.