It should only irritate if the glitter gets in your eye. I know when I use Lustres under my eyes, the glitter usually floats up and bugs them. Maybe don't use it by your waterline??
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I wouldn't suggest using it on your waterline, due to the sparkle particles as they are a bit large. They are eye-safe micas, but I would still err on the side of caution around the waterline. I'd suggest using something like carbon if you are to use a powder shadow on your waterline, and you want black.
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