SI1 & SI2
These stones will be some of the most popular choices among Engagement Rings, because of the price, but it is very important to know the reasons for each difference in price. SI2 and SI1 stones can be thousands of dollars different, depending on the color, size, relief and location of the inclusions. If the inclusion is dark and right in the center of a stone, it should be much less expensive, and for good reason- you will be able to see it with the naked eye. On the other hand, there are some better SI2 stones then SI1, because of the location and color of the flaws.