A clock whose hands appear to float with no visible means of support sold for $295,914 at Antiquorum’s Geneva auction Oct. 16.

Cartier mystery clock No. 2345 sits atop a black onyx base and stands 140 mm high (5½ inches). It’s surrounded by rock crystal quartz, edged in 18k yellow gold. A circle of 18k yellow gold Roman numerals sit above a mother-of-pearl ring, with rose-cut diamonds mounted in platinum beneath. The minute and hour hands are also made of platinum, set with more rose-cut diamonds, and float in the middle. The rock crystal clock is perfectly transparent.

“The Pendules Mystérieuses, or Mystery Clocks, were Cartier’s masterpieces,” says the Antiquorum auction catalog preview. “The results of collaboration of Louis Cartier, his principle creative advisors, and the technical skill of Maurice Couet.”

The clocks were developed after careful study of those created by Jean Eugène Robert-Houdin (1805–1871), the French magician and clock maker.

The catalog explains that each hand is attached to its own rock crystal disc, and the discs are driven by worm screws attached to two lateral axles. These mechanisms are hidden inside the frame, and the movement that rotates the axles is concealed in the base. It’s the discs—one for hours, the other for minutes—that move, rather than the hands themselves.

Image and details courtesy of Antiquorum Auction House