Cartier Clé White Gold and Diamond 'WJCL0015'

At first glance, the Clé de Cartier watch, which debuted in 2015, is a blend of traditional design elements: It has a classic Cartier circular opalescent dial with blue hands and blue Roman numerals, plus an ovoid case that blurs the line between round and tonneau forms, a shape frequently used in mid-century watches.

This focus on design history is not altogether surprising for Cartier (established 1847), given the brand’s penchant for honoring its long legacy of watchmaking. Where the watch becomes atypical, however, is in its mechanical details, specifically in the unusual feature teased by the timepiece’s name — clé means “key” in French.

Rather than the round winding crown that’s typical of contemporary wristwatches, there is a rectangular key, much like the ones found on pocket watches and antique clocks. But in a return to a classic Cartier design statement, the crown is inlaid with a striking sapphire cabochon. Designed in-house by the brand, the Clé de Cartier was also the first watch to feature the caliber 1847 MC, a then-new automatic movement that contains nearly all of the watch’s moving parts.

Although Cartier functioned solely as a jeweler for the first 57 years of its existence — royalty from around the world favored the brand for its tiaras, necklaces, bracelets and rings — it crafted its first watch in 1904 at the request of Brazilian aviator Alberto Santos-Dumont, a friend of Louis Cartier who found that the era’s popular pocket watches were difficult to use while flying. Cartier’s response was the Santos de Cartier watch, featuring a square face designed to sit flat on the wrist, held in place by a leather strap. The timepiece found a broad market beyond Santos-Dumont, sparking the modern era of wristwatches. Since then, Cartier has designed dozens of watches, from the classic Tank line (1917), inspired by World War I–era machinery and worn by such luminaries as Princess Diana and Yves Saint Laurent, to the rare Salvador Dalí–esque Crash de Cartier (1967) and more.

Since the initial launch of the Clé de Cartier, the jeweler has expanded the collection to a number of models for both men and women, with dials ranging in size from 31 to 41 millimeters. Cases are crafted from steel, rose gold, white gold and palladium, complemented by bracelets in identical metals or luxe leather straps. Some more exclusive models feature a full pavé diamond case.

For its extraordinary range of bracelets, watches, rings and other adornments, French luxury house Cartier is undeniably one of the most well known and internationally revered jewelers in the world among clients both existing and aspirational.

Perhaps 1847 was not the ideal time to open a new watchmaking and jewelry business, as the French Revolution was not kind to the aristocracy who could afford such luxuries. Nevertheless, it was the year Louis-François Cartier (1819–1904) — who was born into poverty — founded his eponymous empire, assuming control of the workshop of watchmaker Adolphe Picard, under whom he had previously been employed as an assistant. Of course, in the beginning, it was a relatively modest affair, but by the late 1850s, Cartier had its first royal client, Princess Mathilde Bonaparte, niece of Napoleon Bonaparte, who commissioned the jeweler to design brooches, earrings and other accessories.

Under the leadership of Louis-François’s son, Alfred, who took over in 1874, business boomed. Royalty around the world wore Cartier pieces, including Tsar Nicholas II of Russia, the Maharaja of Patiala and King Edward VII, who had 27 tiaras made by the jewelry house for his coronation in 1902 and issued Cartier a royal warrant in 1904. (Today, the British royal family still dons Cartier pieces; Kate Middleton, Duchess of Cambridge, regularly sports a Ballon Bleu de Cartier watch.)

Cartier’s golden years, however, began when Alfred introduced his three sons, Louis, Pierre and Jacques, to the business. The brothers expanded Cartier globally: Louis reigned in Paris, Pierre in New York and Jacques in London, ensuring their brand’s consistency at their branches across the world. The trio also brought in such talents as Charles Jacqueau and Jeanne Toussaint.

One of Cartier’s earliest major successes was the Santos de Cartier watch — one of the world's first modern wristwatches for men. (Previously, a large number of people were using only pocket watches.) Louis designed the timepiece in 1904 for his friend, popular Brazilian aviator Alberto Santos-Dumont, who wanted to be able to check the time more easily while flying.

Cartier’s other famous timepieces include the Tank watch, which was inspired by the linear form of military tanks during World War I, and the so-called mystery clocks. Invented by watchmaker and magician Jean-Eugène Robert-Houdin and later crafted exclusively for Cartier in the house’s workshop by watchmaker Maurice Couët, the mystery clocks were so named because the integration of glass dials on which the clocks’ hands would seemingly float as well as structures that are hidden away within the base give the illusion that they operate without machinery.

On the jewelry side of the business, Cartier’s internationally renowned offerings include the Tutti Frutti collection, which featured colorful carved gemstones inspired by Jacques’s trip to India and grew in popularity during the Art Deco years; the panthère motif, which has been incorporated into everything from brooches to rings; and the Love bracelet, a minimal, modernist locking bangle inspired by medieval chastity belts that transformed fine jewelry.

While the Cartier family sold the business following the death of Pierre in 1964, the brand continues to innovate today, renewing old hits and creating new masterpieces.

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