As you know, the new higher-end Portuguese movements have blued-screws. They look nice, but there is more to the story
As you may know, there are two ways of making screws blue. The first, and more common, way is chemical treatment. The screws are dipped in a bath, and in effect are painted.
The second, and more costly, way is to heat treat the screws. The screws are exposed to a flame until a specified temperature which causes them to discolor. This hardens the screw, and also is the more traditional way. It requires more handling but the true connoisseur finds this more special.
What does IWC do here? I asked Walter Volpers, the new head of Product Management at IWC, and he gave me the simple answer: heat treatment.
