Ugh, glitter... It's, it's great stuff. You use it for one art project and suddenly it's everywhere, it's on your clothes, in your hair, clinging to your arms. And just when you think you finally cleaned it up, you find a little more stuck somewhere. So, how and why these tiny, shimmery, plastic particles so sticky?

Well it turns out, it's probably a combination of a couple of different factors, like static electricity and good, old-fashioned van der Waals forces. Van der Waals forces are weak electrostatic forces between uncharged molecules. They're why water forms droplets, why geckos can run up walls, and why tape is sticky.

See, even though a piece of glitter looks like a tiny flat disk to us, all surfaces have microscopic bumps. So the molecules on the surface of the piece of glitter are going to interact with the molecules of whatever it's sitting on. Even though uncharged molecules are electrically neutral, sometimes they can be dipoles, with a slightly positive charge on one side and a slightly negative charge on the other. The dipoles attract each other, like how water molecules stick together. So, when glitter ends up on your skin, which has some water molecules hanging around, the glitter and water attract and you're stuck being sparkly. 

And when glitter is just sitting on any surface, those van der Waals forces are also creating very weak static friction. Just a tiny bit of resistance. Since glitter pieces are so light when you try and brush them off a surface, this resistance is enough sometimes that some won't slide off so easily. Plus,if glitter does rub against another material- say skin, cloth or fur- some negatively-charged electrons might jump from one material to the other. One material will become slightly negatively charged, and the other will become slightly positively charged, so they will stick together because of static cling.

So, be careful when you craft. It is really, really hard to get rid of glitter completely because of science. 

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