The gemstones can be of equal size or the centerpiece diamond in the three stone setting could be larger than the side stones. A good thing with this diamond ring setting is that you could go for colored gemstones as the center stone and white diamonds placed on each side. That could look make the center stone look gorgeous and more pronounced. Yet again, you could also go for a white diamond centerpiece and choose colored gems on each side to get the same kind of accentuated impact. No matter which three stone diamond ring style you choose, the symbolism of the past present and future ring remain intact in both. Another thing to consider while choosing a three stone diamond ring is the precious metal. Ideally, you would want to consider the color of the gemstones to make sure that the metal blends well with that. If you are choosing colored gems, for instance, white gold could be a good option. On the other hand, if you are going for rose or yellow gold or platinum metal band, choose gems that complement the design.