I suspect it was not painted as such but was coated in a bronzing
powder operation.  After the fillers and a ground color was brushed
on and smoothed out it was then varnished, and when the varnish was
tacky powdered bronze flour was sprinkled on, the excess swept off and
the surface burnished when dry.  Then additional varnish with perhaps
a tinting color was applied to protect it.  Shellac and alcohol based
products may have been used as well.  In short, it will not like modern
solvents being applied over it.

The bluish tint may not be the original color but could well be some
of the bronze powder near the surface corroding with bluish verdigris,
resulting in the color shift.  Any tinting is likely in the final
varnish colors on top.  Try wiping with denatured alcohol and see if a
clean rag comes up bluish in color once you get the brown dirt staining
of the ages off.

Age changes most paint surfaces.  I once consulted on a Victorian
house where the owners had reproduced the fancy original stenciling.
It was mostly maroons with black highlights in what they had
reproduced.  Thankfully they had not gotten very far and were pleased
to be told that the odd black had been bright gold which had completely
corroded between air contact when new and then having wallpaper paste
finish turning it black.  If it looks really wrong, it probably is
really wrong.

It may be possible to clean and touch up missing coatings, although you
likely do not want to take on 100 hours of work if it is missing huge
amounts of finish.  Otherwise, a total repaint may turn out to be
expedient solution, based on whether your new paint is also a stripper
and wrinkle medium of the old surface, you may also need to strip down
to stable under layers.

Good luck and go slowly,
Bill Frisk