If you were looking to purchase a round diamond ring, the most important thing to look for would be grading of the diamond. The grading can determine how well the stone interacts with light and sparkle. Other aspects like depth, pavilion depth, crown angle, girdle, and culet determine the grading of a round diamond.
Color is the next major thing when choosing a round diamonds engagement ring and is something entirely depended on your preferences. Diamonds in the range of D to F are colorless and can quite well match with any kind of ring metal or settings. Opting for a round diamond below the scale of K can give you slight gradations and hues in the diamond. Moreover, it is better to choose a diamond with color grading between D to G if the stone has less than 1.0 carat.
Besides, you need to look for the clarity grade of the round diamond before selecting it for your ring. Choosing the perfect clarity grade is important if you prefer to have a diamond that is flawless and does not contain any inclusions. You can choose a low clarity grade to make up for the price and get a diamond with no flaws at all.