Dear watch aficionado.
Here a nice example of a Patek Philippe 2584 with black épargne dial, of which only two examples are known:
The dial is made by Cadran Stern with the complicated "épargne" technique, which means that first the base plate is gilted, then the signature, minuterie and small seconds are protected by a special lacquer, after that the dial is colored in a black galvanique bath. After the black color has dried, the protective lacquer is taken off. Later the hour baton indexes and the 12 o'clock indexes are added. The indexes are fixed by "pickage" and then leveled by "limage" as you can see on the photo of the dial from the back. This method called "pickage & limage" was used back then at that time. These methods, "épargne, pickage, limage" can be seen as well on famous dials as the Bao Dai.
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