GS Grand Seiko

Zirconia ceramic: light,
strong and scratch-resistant

Of the many types of ceramic that were tried, zirconia ceramic had the most potential. Like its close relative, cubic zirconia, which is widely used in jewelry, it is very hard and light and has a unique deep brilliance. Its greatest asset, however, was also its greatest challenge for the designers and engineers charged with making the zirconia ceramic case. Its hardness made it very difficult to machine and the team needed many months of experimentation with manufacturing processes before they achieved their aim.

The ceramic prototype (right) and the completed component (left). After much testing, the team succeeded in creating elegantly flowing curved surfaces and a polyhedron profile.

High water resistance is just the start

The Grand Seiko diver’s watch was specially designed for maximum durability, in two important respects. First, it was designed to withstand the shock and rapid changes in temperature that can occur in sports situations. Secondly, it was designed for the long term in the sense that the design of the movement and the casing allow the watch to be disassembled easily so that maintenance and the replacement of components can be done safely and simply.

Cross-section of a diver’s watch case with a Spring Drive movement