Harry Winston Histoire de Tourbillon

Histoire de Tourbillon is an experimental line from the jewellery house Harry Winston, begun in 2009: tourbillons whose carriage rotates in several planes at once. The brand itself places the series in its Haute Horology category.

Two examples are the Histoire de Tourbillon 7 and Histoire de Tourbillon 8. They share a common base: both are men's models with a 51 mm white gold case featuring Harry Winston's signature arches, and on the left half of the dial two bi-axial tourbillons work together, linked by a spherical differential.

The models differ in movement and in how the time is displayed. Calibre HW4502 of the seventh edition runs at 21,600 vibrations per hour, and the hours and minutes are offset to the right, on the skeletonised part of the dial. The eighth edition uses calibre HW4503: each carriage completes a rotation around its outer axis in 75 seconds and around its inner axis in 45. Here the time is shown by two cone-shaped discs, and a sapphire caseback reveals the movement from behind.

The choice comes down to the display: offset hands on the openworked part of the dial on No. 7, or discs on No. 8. Both dials are black with anthracite grey. No. 7 also has red on the dial and an alligator strap with red stitching; No. 8 has a black leather strap. The brand's other lines are Ocean, Premier and Midnight.