What metal is the dial of Constellation Pie Pan 14900 made of?

Hello everyone,

I have a 1961 Omega Constellation Pie Pan 14900 with a silver (white) crosshair dial and I'm wondering which metal Omega used for the dial itself. Is it brass or something else?

I'm asking this because, in the case of a vintage Cartier Tank, I once witnessed a small rust dot appearing on the dial after wearing it for a long period, possibly in a humid environment. A vintage Cartier specialist told me it was rust, indicating that the dial was likely made of non-stainless steel (?)

What about the Constellation? Could something similar happen? There are already a few small dots from the past, but they appeared before I acquired the watch, and I'm uncertain about the reason.

Thank you.

I think in this period Omega used only brass or aluminium.

Thank you! If this is correct, sounds good 😀

From my limited knowledge rust on ferrous metals is worse as it "grows" on the surface changing its structure and can eat through the (porous) paint on the dial. Other metals may oxidise especially at the places where lacquer on the dial is damaged (exposed metal), but I imagine it is somehow less harmful as it creates just a dark layer on top of the metal (it could react with the lacquer over the time though). I may be wrong...