When it comes to celebrity engagement rings, the stars opt for the biggest, most expensive diamonds they can find. We're talking millions of dollars just resting on Kim Kardashian and Mariah Carey's fingers! Fortunately, Beyoncé is a bit more practical with her million-dollar band. Like a true Virgo, she bought a cheaper replica that she wears all the time and keeps the real thing in a vault, you know, since it is a $5 million investment. But forget price for a moment, who has the biggest jewel, the coolest cut, or the most unique design? We took stars' rings and placed them in a head-to-head battle. Below, a visual rundown of the results.