The table below points out what the labels mean, such as IF, VVS, SI, etc. Until this point you probably thought all diamonds were clear, or white crystal looking things. Look closely at the color of the diamonds you're considering purchasing. Most girls want it as white as possible, but a little color is not noticeable. Now, it's getting easier.
Many girls have a favorite shape that they've dreamt about for years.
It might be a good idea to find out what your future wife's favorite diamond shape is. Or, you can just be random and choose what you think she'll like. Remember that cost is not dependent on size. If size is most important to you than go for it. However, we think most girls would prefer a little smaller size rock that has better color and clarity.