The Rotonde de Cartier Earth and Moon features what Cartier calls a “secret” moon display. The round tourbillon at 6 o’clock represents the disk of the moon. With the push of a button, a blue disk covers as much of the tourbillon as needed to represent the current moon phase. The display at 12 o’clock indicates two time zones. See more images and specifications here. See our original write-up of this piece on the page linked above. The Earth and Moon will be produced in a limited edition of 50 pieces in platinum with a lapis dial priced at 200,000 euros.