Could you please help with Dating my Atmos Clocks, the first one S/N549033 probably from late 1982 or early 1983. It is Caliber 526-5, it has a silver colored casing. My Question regarding the case what material is the plating? Would it be rhodinium or nickel or chromium? The second Atmos S/N 23717 is Copper colored (or is it rosegold?) it has the Serial number on the top, according to the info I found in this Forum it should be a Atmos 2, however the pendulum is a Typ B (with dimpels and not black Stripes), It has blue screws and the Adjustment regulater knob towards the front. I wonder how many Clocks were produced plated in Copper at the time? Thanks for your help!