There are only two things which you pay for in diamonds. One is how big they are and the other is how bright they are. On the next page we will give you a short explanation as to weight of diamonds and in the following few small pages we will try to give you a different but much easier way to look at how bright diamonds are and the grading systems that are used. Brightness (Quality) is determined by the heart. Only size is determined by the depth of the purse.