From the manufacturer:
Let your ideas sparkle with Gelly Roll Stardust® pens. Why fuss with glitters and glue when you can write with glitter ink directly from a pen? The bright colors and shine make Stardust® ideal for applications such as cards, notes, and paper crafts, and the archival quality ink* ensures that letters and scrapbooking pages will last for years. Give your handwriting a special touch that can't be reproduced by digital printers. For the best results, use Gelly Roll Stardust® on light-colored, matte paper surfaces.
Gelly Roll Stardust is a pigment-based archival quality ink and is indicated in each color name with the suffix "-STAR".