Blancpain - FP 1185 Movement

Dear members,

i have question conserning the Blancpain F185 movement (Frederic Piguet 1185).
This movement has been used also by big brands like Audemars Piguet and Vacheron Constantin.

On several ressources i found people stating, that the Blancpain F185 automatic rotor mass is made out of solid Gold. However looking at the online photos i couldnt find any indication on the rotor stating its Karats.
Therefore i am interested to know if this is actually a gold plated rotor mass or did they use solid gold on those?
Thank you!



The AP and VC clearly have the gold rotor and they are also marked as such "18C".

Vacheron Constantin caliber 1137


Audemars Piguet caliber AP 2385

I can agree with this, however when i look at the limited editions of the same Model (Lemand Flyback Chronograph) and some other models from the same era and they do indicate the "18K" Gold.



I also heared Tim Mosso stating in some Podcast that JLC started Gold plating their Tungsten Rotors for cost saving, therefore i started looking into this topic and if there are other manufactureres that do this practice.
Its interesting since a lot of reviewers mention the solid gold rotor on JLC, but is it becuase of ignorance or is it really so?
It would be strange to actually use solid gold and not to indicate it anywhere.

For example the older generation of JLC cal. 899 has a "22C" indication.



The modern JLC cal. 899, has no sign or whatsoever.

Didn't know about the gold and tungsten thing. Gold plating the rotor just feel... cheap. Would never have expected JLC to do that.

I dont know where Tim Mosso got his information from. But since he is in this business for fairly long, maybe he has some reliable sources.

Here is a new video review from WatchAdvisor on Youtube:

He mentiones (2:40) that even though the rotor on the new Master Control line has no indication on the rotor, it is in fact a sold gold and that the stamp is apparently on the back side of the rotor. I think he asked the manufacturer directly. The resoning is that the manufacturer decided not to put it on the front side, due to design reasons. Would be interesting to see the back side.


I was so curious that i took off the rotor on my Leman to see if there is an indication on the back, but there was nothing. it does not look like plating, especially if you look at the scratched places, and would make not much sence to gold fill it, so i am rather thinking it is in fact solid gold.. but it still remains a mystery why they would not indicate it.

Nice looking movement there 👍
I have never seen Blancpain using blued screws before.

That's my 2185 (with FP 1185) and I would say it hasn't a rotor made of gold, or at least it isn't hallmarked as gold.

yeah, really strange considering its a solid gold watch. i guess one will have to drill a hole in order to find out 😁

Unless it's marked because it's white gold, in order to avoid confusion, while yellow gold is supposed to be evident.
Don't know, just an hypothesis.