I have the pattern to make this buckle but how in the world do I make "gold" or "Silver" Fondant????? What else can I do to get this job done???

I'm not a pro at fondant, but I would paint it with luster dust & either vodka or lemon extract after I'd shaped it into a buckle.

Colour the fondant yellow or gray first, gives a stronger result. Then as was said, mix lustre dust with alcohol and paint.
xx

Thank you both so much !!!!!!!!!!!!!!!!!!!!

luster dust or airbrush.