Diamonds are mainly graded according to the 4 C’s: Color, Cut, Clarity, and Carat. The carat of the diamond solitaire engagement ring is a factor that highly determines its cost, and choosing the carat of the diamond is purely your choice.
The color of a diamond is graded from D to Z; where D to F is colorless diamonds, and as you go down from F to Z, the color will have more and more yellowish tint. To the naked eyes, H, I, or J grades have the same appearance as that of colorless diamond, and hence buying it would be less expensive.
Clarity is a factor that determines the presence of inclusions within the diamond. Diamonds with FL and IF clarity grades are at the top of the scale. However, you can opt for a diamond solitaire engagement ring with SI clarity range that looks as clean as the FL and IF to the naked eyes.
Cut of the diamond is the aspect that determines how much brilliance and sparkle the stone exhibits. You can choose a diamond ring with diamond cut rating Good, Very Good, or Excellent on the grading scale. Note that the grade Excellent will be the most expensive.