I have no idea what this is used for. I tried it on my face, and I got a lot of sparkle, but that's all I can see a difference of. I'm not sure what its function is perse. In my opinion, it's fine for clubbing, or keeping your face looking shiny, or metallic, but not an everyday using product.
Since I received this as a gift from Sephora, I'll continue to use it. However, I wouldn't go out and buy this on my own. I don't see what the great thing about it is!

Makes a perfect natural glow! I love it! I've gotten so many compliments on my skin, and "glowing" complexion that I use it everyday.
It can be used over or under makeup, but have found that putting it on before foundation makes the skin look more illuminated. It appears thick and dark, but applies sheer and is very lightweight.
Gives even more oomph to your complexion when used with a little blush.