Apparantly there is no mauve petal dust...just luster dust. I need to dust some off-white roses with mauve. Do you think if I add some purple to pink, I could get mauve??

yes, or purple and orange.........sounds odd I know, but by complete accident I made the most beautiful shade of mauve by using bright orange icing and mixing it with purple icing ( I was just practicing some flowers and was using old icing that was leftover, various colors)

Get some chalks from the art department at a hobby store. Shave them down. Mix and blend for achieved shade.