GILDED - PAINTED FURNITURE
The varnished (painted) piece of furniture "arte povera"-plain art- is a different event. A few painted or gilded furnishings with paper card stickings (Venice and Rome XVIIIth. century) get intact to us. Most of them have been re-painted in nineteenth-century, some badly, because of their degradation. It is almost impossible to find a piece of furniture with the original paint.
The ones that are find are fakes with the painted layer done by chimical means to imitate the antique.
The pictorial coat existing on top of the wood is very thin, the thicker it is the older is the piece of furniture.
Moreover to test the authenticity, look at the craquč, that is to say the deformation that time left on the paint creating those small cracks (as in a painting of XVII-XVIIIth. century that shows the pictorial layer degrade with small liftings and dehydration), check the hardware and the artisan work.
For what concerns painted furniture with paper cards stickings on some information could come from the paper used , from the colour and from the sandarach coat.
The restorer who has to restore a furniture re-painted in XIXth. century, has to use all his professional experience before removing the various coats covering the original one (that are often different one from another) using neutral solvents, to reiforce the original paint, then to do the pictorial restoration .
During my long career as a restorer I often saw furnishing in "arte povera" of the beginning of eighteenth century, but only once it happened to me to see a roman piece of furniture (high Lazio of 1750) with eight coats of varnish put above of different colours of synthetic varnish, the last one an orange peel like. Under all that varnish there was a magnificient light-ash colour paint with various antique ivory shadings and little paper cards which were real miniatures.