Blow on a empty pop can sounds like Crystal Glass?

I can blow on a empty Pop Can and make a tune, it sounds like Crystal glass when you make it sing. I’m just wondering how and why it does that? Any one know how to do that and know why it does that? I bet i’m not going to get that much answers, Well don’t know in tell i do it. blowing on a empty Pop Can and sounds like Crystal glass, Any one know why it does that, No one? Okay thanks any way.