In 1917 Pierre Cartier traded a double-stranded natural pearl necklace and $100 in cash to banker and railroad tycoon Morton F. Plant for his neo-Renaissance mansion at Fifth Avenue and 52nd Street in New York. The deal caps the story of three grandsons who turned a Parisian workshop into a global house. Louis, who took over Paris around 1899, pioneered platinum in fine jewelry, letting hair-thin settings hold diamonds that seemed to float, and with watchmaker Maurice Couet built mystery clocks whose hands sat on clear rock crystal disks. In 1904 he made the flat Santos wristwatch for Brazilian aviator Alberto Santos-Dumont, and in 1919 the Tank, modeled on the top-down view of a Renault tank.

Pierre opened New York in 1909 and sold the Hope Diamond to Evalyn Walsh McLean by leaning into its curse, while Jacques ran London and sourced stones directly in India. Clients ranged from Tsar Nicholas II to the Maharaja of Patiala, whose 1925 order is put at roughly 2.1 billion euros today. After Pierre died in 1964, the heirs sold the Paris, London and New York branches to separate investors. In the 1970s Robert Hocq led a syndicate that bought them back and reunited them; Hocq and Alain-Dominique Perrin created Les Must de Cartier, a line of lighters, pens, sunglasses and perfume, and after Hocq died in a 1979 car accident in Paris, Perrin led the company into the group that became Richemont.

• Louis Cartier’s mystery clock work culminated in a 1933 patent for the invisible mount.
• King Edward VII ordered 27 tiaras for his 1902 coronation and is credited with calling Cartier the jeweler of kings.
• The Love bracelet, introduced in 1969, is screwed onto the wrist with a tiny screwdriver.
• From 1976 to 2003 the Cartier name was licensed to Ford’s Lincoln Continental luxury cars.
• Michael Douglas wore a solid gold Santos in the film Wall Street as a corporate raider’s status symbol.