If you're an artist, everything is a medium. And for Andoni Bastorrika, that's sand. That's right, while most of us feel really good about ourselves after we build a castle at the beach, Bastorrika isn't content with that.

If you're an artist, everything is a medium. And for Andoni Bastorrika, that's sand. That's right, while most of us feel really good about ourselves after we build a castle at...