Here is the big difference: Star Bites are a larger particle size, about 100-260 microns. This makes them somewhat more sparkly than Sparks! which range from 20-200 microns. They are particularly suited for nail lacquers.
Moon Dusts are a smaller particle size, 30-120 microns, while they are suited for nail lacquers, they are particularly suited for use in eye cosmetics.
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