Bernard, when I look at the head (eyes+beak) of your pigeon/dove, then I would say that this could very well be Marcolin.
Looking at the grey effect, then I would say that this could be Marcolin or V. Nason.
The fan tail? Well, that suggests Formia.
I haven't seen the exact 'fan tail' in any of Marcolin's or V. Nason's birds but then I haven't seen everything made by Marcolin or V. Nason.
Regarding the eyes, from what I can see Formia now often use applied eyes but how about for instance 30 years ago? How did Formia's birds look then? If your pigeon/dove was made ?years ago (1970's?) then it does not give a correct comparison to look at Formia's birds of today.
And what about the colour of the dark inner core?
There are so many things to compare, and depending on when the item was made it can be very difficult to determine who made a certain object. Objects made in the 1970's does not look the same as the ones made today!
And the grey effect? When did Formia start using this grey effect?
Bernard, if you ever decide to sell your mystery bird ..... please let me know!
I included a picture of a dove in "post #20", here is another dove from Marcolin for comparison.