Mystery clocks, with hands that appear to float free on the dial, have been part of the Cartier heritage for more than a century. Today, Cartier has developed the Mysterious Double Tourbillon that appears to float free at the heart of the Rotonde de Cartier watch.
The watchmakers of the Cartier manufacture have employed a disc of sapphire crystal with an anti-reflective finish containing an aperture the size of the tourbillon to give the best possible illusion of a cage in a state of levitation. To do this, they set the disc to support the cage in rotation. By doing this and positioning the minute wheel, which propels the oscillator, on the axis designed to limit the “resistance torque” inherent in the mechanism supporting the tourbillon, they succeeded in transmitting its force to the tourbillon, and thus causing the entire device to revolve in space once every 5 minutes. This results in the tourbillon making one full turn of the open, transparent space in 5 minutes, while the cage performs 5 complete revolutions in the same time... The ingenious way of achieving such a result is to place a rack around the edge of this sapphire crystal disc, transforming it into a large gear wheel that performs one revolution every 5 minutes.
The sapphire case back of the Rotonde de Cartier also reveals a part of its movement, allowing watch lovers to admire the finish of its components and observe that the caliber 9454 MC, with a thickness of 5 mm, carries the Hallmark of Geneva.
The Montre Rotonde de Cartier Double Mystery Tourbillon comes in a 45 mm rose gold case. The watch is fitted with a brown alligator skin strap with a double adjustable folding buckle in 18-carat pink gold.