In the piano restoration business we mix our own gold paint for piano plates, screws,etc. I purchase "bronzing powders" from the manufacturer. I keep 6 or 7 different shades. There are probably 100 shades or more available including green, red, blue, yellow, and other odd metallic shades. I have two gallon cans of the shade I use to match most old upright piano plates. I was afraid they might discontinue my color, so I bought enough to last me another 30 years. Gilding a piano plate takes about a tablespoon in the spray gun.
To get the true gold leaf look as done on antique furniture and light fixtures, mix the powder with orange shellac and paint it on. When done and dried, coat with 2 or more coats of orange shellac. This technique was done on many, many cast iron light fixtures, dictionary stands, etc.
Doug L. Bullock, copyright June 18, 2009