You can see the detailed Diamond Color Grading Chart below:
Color: D, E, F – Colorless Diamonds
Color: G, H, I, J – Nearly colorless diamonds. But it appears colorless when set into a piece of Jewelry.
Color: K, L, M – Faintly tinted diamonds. Usually we can see say yellow tint.
Color: N, O, P, Q, R – Very lightly tinted yellow diamonds. But you see it that color is visible to the eye.
Color: S, T, U, V, W, X, Y, Z – Light yellow diamonds. Color is very visible to the eye, even when you set into Jewelry. Fancy Colors are graded according to a different scale.