Diamond color
Traditionally, diamond color is actually graded on lack of color -- the best diamonds are almost clear. The hues graded in "white" diamonds are actually faint tones of yellow, brown and greys. An alphabetical scale from D through Z is used to express the color. Imagine two glasses of water -- one clear, the other containing a few drops of lemonade -- and you will begin to get an idea of the differences in diamond color grades. The following color scale is an approximate representation of color saturation in diamonds: D-F: Colorless G-I: Near colorless J-K: Faint color L-R: Noticeable color S-Z: Obvious color

Diamond clarity
Clarity is the grade that describes the inclusions and blemishes of the diamond. The fewer inclusions and blemishes, the more valuable the diamond. Clarity can also have a direct impact on the stone's brilliance. Inclusions in the diamond can block the light from reflecting inside the stone, which is the feature that gives diamond jewelry its brilliant beauty. The following diamond clarity grades are listed from best to least and are based on the observation of a trained gemologist: FL (flawless): No inclusions or blemishes of any kind are visible inside or outside the diamond under 10-power magnification. IF (internally flawless): Diamond has no internal inclusions seen under 10-power magnification but has some external or surface blemishes such as a miniscule scratch. VVS-1 & 2 (very, very slightly included): Diamond with inclusions so minute that a trained gemologist has significant difficulty seeing them in the diamond under 10-power magnification. VS-1 & 2 (very slightly included): Diamond has minor inclusions which are moderately difficult to see under 10-power magnification. SI-1 & 2 (slightly included): Diamond has inclusions somewhat easily seen with 10-power magnification but extremely difficult for the gemologist to see without magnification. SI-3 (slightly included): Stones that fall right on the border between SI-2 and I-1. I-1, 2 & 3 (included): Diamond has inclusions that are noticeable without magnification.

Diamond cut
Cut is divided into shape, proportion, polish and symmetry. Shape and proportion are all of great importance when cutting a diamond to its best appearance. Shape and proportion affect how a diamond "scintillates" or shines because it affects how light is reflected and refracted inside the stone, which is what causes diamonds to sparkle. Depending on how deep or shallow the diamond is cut, the face-up appearance of the diamond can also vary greatly. The polish describes how well light enters and exits the facets of the diamond. Symmetry can describe both length to width ratio and also depth percentages. "Ideal cut" is the best.

Diamond carat weight
Carat is a weight measurement of diamonds. It is abbreviated "ct" or "CT" when describing a single stone. "TDW," meaning "total diamond weight," is added when the diamond jewelry is set with multiple diamonds. For example, a solitaire diamond engagement ring may be describes as "1ct" while a 3-stone diamond anniversary ring would be 1ct TDW. (Note: Carat is not the measure of gold's purity; that is spelled "karat" and is abbreviated "k." So, you may have a 1ct diamond in a 22k setting.) It is difficult for most people to equate carat weight with an actual size. Therefore, we have included a brief guideline for comparing carat weight to millimeters. In this example, we use round and princess ideal cut diamonds. Differences in the diamond shape, depth and cut of a specific stone will mean significant variations from these sample measurements.