Floydianoise , 'gilding' or 'gilded' gold is a term that describes (generally , anyways) a process of applying actual gold leaf (gold that has been hand-pounded into extremely thin sheets) to surfaces .
It's a very dainty process , when used on wood/gessoed wood (cold/room temp process) - not the same process as is used with metals (usually a hot process with those types of items) .
There have been many grades (purities) of gold used for gilding through history ; there are current alloys that appear to be gold , but are not !
Brush-painted wood frames will have distinct 'brush-stroke' patterns , when viewed under 10x or more magnification , as well as having some small-to-large areas (that were not intended to be painted) where you can distinguish a singular (or more) bristle-stroke .
Gilding is sometimes done over hand-applied gesso , which will sometimes be confused with painted items , since the brush-strokes in the gesso will 'show' through gilding as if it is a painted item .... all that being said , gilding is done with natural bristled brushes , which can add to the confusion of identifying with unexperienced eyes !
As KC stated in his post above , sometimes it was in a powdered form too ( I missed that while posting this entry ) .
Often times this type was very fine powdered copper , with a plaing applied to the grains of powder ( looks like gold-dust , in it's raw form ) .
