Painting Mirror Frame

I'm considering painting the frame of a recently purchased mirror as think the finish may be too ornate for the location. It is a dull gold and I can't tell if it is wood or perhaps jesso. I want to tone down the gold and was thinking of using a "wash" of cream paint as I'd like a hint of the gold to come through. Do you think this would lightly cover the gold? What percent water vs. paint should I use? Should I put it on and then wipe some off lightly? Should I apply something to the original finish before trying to paint over it? Lightly sand? Thank you for any assistance you might offer.

 

Sorry it took so long to post back.

You might try lightly scuffing it with fine steel wool, giving it a 'rustic or antiqued' look.

You could try brushing on a color, and gently wiping back off, leaving the high spots gold.

Or maybe try a glazing liquid to go over it like a 'colorwash'.

Your project will probably be mostly trial and error, experimenting until you get a look that you like.

Sorry I couldn't be more specicf, I generally don't do faux finishes.