In the mid-1980s, IWC paired some of its flagship and innovative Da Vinci models with zirconium oxide cases. Although several colors were used in prototypes, black or white zirconium cases were used in limited production.
Then, in 1994 through 1999, IWC produced its automatic Fliegerchronograph model (Ref. 3706) in a black zirconium case. This new model, called Ref. 3705, was produced in 999 examples, and today is highly collectible.
These ceramic models had no ordinary cases, but instead used a new generation of ceramics that had nothing to do with either pottery or bricks. Known as fine or engineering ceramics, these materials include any hard, non-organic, non- metallic substance which is sintered at extremely high temperatures and fused with other elements.
To fabricate these cases, a complex process is required. First, a powdery substance of extreme purity is mixed with chemicals to change color. A binder is added to the colored raw material, which then is molded in the shape of a pre‑blank.
A case blank is then cut from the pre-blank, using special tools, which then is put into a kiln to produce zirconium oxide at very high temperatures. The microfine powder grains are actually baked together.