I need to color/paint fondant to make it look like a greenish/black champagne bottle.
What color lust dusts or other colorings do you recommend?
Do you mean this type of colour?
I would experiment with dark greens and a very light use of black lustre dusts, maybe you could have a "test" piece of fondant and mix the green with the black or paint the green and then a little bit of black over the top?
The green in the picture looks like the right colour and they say they have just used dark green? so maybe you just need a dark green lustre dust.
Hope this helps! Good Luck!