If you're including something that's gold or silver, such as an ornament, in a painting, the first thing to do is to forget that it is metal and just try to analyze the various colors you see in the light middle and dark areas. You need to look into the light areas and dark areas (tones) and try and decide what colors are there and paint these.
For gold, I would use lemon yellow, yellow ocher, burnt sienna, and ultramarine blue to mix the darks. Silver will be varied grays but will also reflect any colors close by.
Remember painting is an interpretation not necessarily a photographic reproduction, you are allowed to be creative in that interpretation.
Tip from: Dave Armstrong
For gold ornaments I use, raw sienna, burnt umber, cadmium yellow, and white.
Tip from: Papaya