Hope this may help;
I have been using glitters of all descriptions for years including for mixing with l+p.
the best glitters to use IMO are polyester based, these are the glitters that are also suitable for skin aplication.{recomended by the London Collage of Fashion}
These tend not to bleed as they are designed for use with multiple adhesives and chemicals.
A great indication is to stick with scrapbooking stuff, or look for anything acid free!
A great new range has come out by "do craft" they have loads of colors and do standard, glitter dust and strand glitter it is GR8 x