Different than the other categories, I've divided rings into two sub-categories. Cocktail rings are much like statement bracelets, they can be worn with statement earrings. A cocktail ring could be in a coordinating color to your outfit or a detailed design. You would most likely wear this on a night out or a party. Shop ring 1 and ring 2. (ring 1 is no longer available; here is another option for a colorful cocktail ring.)
Casual rings are ones that you would wear day-to-day. They could be stacking rings that can give you different kinds of looks. Or it could be a classic design that goes with everything. These rings can be worn with any type of outfit and any type of other jewelry. Shop ring 3 and ring 4.