Bianchet debuted a sports tourbillon in a modern 43mm x 50mm case upon entering the watchmaking industry and captured the attention of horology fans with the tonneau-shaped case made in modern materials, the all swiss-made, in-house movement and a perfectly balanced aesthetical appeal which is driven by the founder's fascination with the work of the Italian mathematician Fibonacci and for the Golden Ratio (1.618). First the case, followed by the spiral-shaped movement, the Tourbillon B1.618 Openwork is a masterpiece ruled by the golden ratio, in the likes of Da Vinci’s “Mona Lisa” or Aston-Martin's Rapide S.