I want to create a rustic look on fondant like in this picture by toneda
http://cakecentral.com/gallery/1160460
How do I create this look? I am just talking about the old rustic look on the fondant. Do I just use petal dust of different tones? I plan on using white fondx fondant and gold petal dust. Do I need multiple shades of gold? Thanks for your help.

Multiple shades would give you more variance, which would help the over all look of it.

Looks like she used a green fondant base then brushed it with gold or bronze lustre dust -- heavy in some places, lighter in others. You could start by marbeling the fondant then brushing the color dust you want over it. Remember, when you are going for a look like that, the more you play with it the worse it looks. Those looks generally come together rather quickly and for a rustic impression, you don't want it "perfect".

Usually you want three tones of one color: base color, one shed lighter, and one shade darker. Color entirely with base color and add highlights and lowlights with the other tones. An additional antique effect can be done with different colors to add to the old look and effect - looks like what she's done here.

Tips:

Look up painting techniques for antiquing and aging a piece for a style that works for you.

Try it on a sheet of paper or scrap of fondant before the cake. Relatively easy technique - but use a light hand. Too much is too much. It often helps to walk away from it for a few minutes when doing any antiquing method so you don't put too much on.

Thanks so much for your help. I have ordered 3 different gold, a light one, a dark one , and a broze looking one. I am going to share everything when I finish the cake. I am too excited. I am going to use a white base because it's for the golden anniversary. Should I use a colored base?