Lucien Steinmann, co-chief executive of Positive Coating, said A.L.D., as the process is commonly called, involved applying a transparent coating of oxidized metals onto a surface, atomic layer by atomic layer, in a vacuum chamber. “Due to the thickness of the coating used for decoration on dials, cases and movement parts, the human eye will experience different colors,” Mr. Steinmann said. “It is the same visual phenomenon as when you see different colors in an oil stain in a water puddle.”
Most recently, Positive Coating used this process to create the purple hues in the Faubourg de Cracovie Purple Panda ($32,800), presented in March by the Geneva-based watchmaker Czapek & Cie. Mr. Steinmann said the handmade guilloché dial on the 41.5-millimeter chronograph was coated with 50 nanometers, or 0.00005 millimeters, of the transparent material for a purple effect.
“I always keep an eye out in trendy cities around the world — what do people wear, how do they behave and act in cities like New York and Tokyo?” said Xavier de Roquemaurel, chief executive of the brand, which was introduced in 2012. “So, when one of our collectors and shareholders suggested purple, it made perfect sense.
“But it is not a huge thing,” he added. “Out of our total production, which in 2022 will be around 600 pieces, we have made 18 Purple Pandas, which are all sold out.”
The latest iteration of the 39-millimeter TAG Heuer Monaco chronograph — released this month and called the Purple Dial limited edition ($7,150) of 500 pieces — also featured the color. But the brand, owned by LVMH Moët Hennessy Louis Vuitton, used a spray-painted gradient dial that ranged from a light purple in the center to a dark eggplant at the perimeter, as well as a purple column wheel, purple details on the oscillating weight and a purple lining for the alligator strap.
