Cf. their discourse on the duometer movement, which was perfect balance with few complications, and then, thanks to the Helvetic holy spirit... that's no longer the case, and you can add all kinds of stuff without affecting regularity....
I just note that JLC is abandoning the German Silver on the latest Duomètre and that at the same time ALS - which belongs to the same group - is still promoting this finish....
About Brass : One of the enticing characteristics of brass jewelry is its gold-like appearance. Depending on copper-zinc ratio, the color of brass may range from dark brown to silvery white. To achieve a gold-like shade, you must combine around 67% copper and 33% zinc. Thanks to this unique property