Today, the international color scale from GIA (Gemological Institute of America) is used to grade diamond color. The scale ranges from D to Z:

• D, E, F (Colorless): These diamonds are completely colorless and ice white. They are very rare and command the absolute highest prices. D is the finest grade of all.

• G, H, I, J (Near Colorless): These diamonds usually appear completely white to an untrained eye, especially when set in a piece of jewelry (e.g. white gold or platinum). This is the most common color category for engagement rings because they offer a fantastic white sparkle at a more affordable price.

• K, L, M (Faint Color): These stones have a very light, subtle tone of yellow or brown, which is especially noticeable in stones larger than 1 carat.

• N to Z (Very Light to Light): These diamonds have a distinct, visible tint, usually in yellow or brown. These diamonds are valued lowest on the market.

In the past, and to a large extent still in the Nordic market, an older system with terms like River, Top Wesselton, and Wesselton was used. Although GIA's letter scale is the industry standard today, you will still often see these terms at Swedish jewelers. Here is a translation:

• River: Corresponds to GIA D and E (Colorless/Ice white).

• Top Wesselton: Corresponds to GIA F and G (Rare white).

• Wesselton: Corresponds to GIA H (White).

• Top Crystal / Crystal: Corresponds to GIA I and J (Slightly tinted white).

• Top Cape / Cape: Corresponds to GIA K to M (Tinted white / Yellowish).

An interesting aspect of a diamond's color is how the metal it is set in affects how the eye perceives it. An H or I color diamond (which theoretically has a very light warm undertone) can look dazzling white if set in yellow gold, because the gold itself is warm. If the same diamond is set in platinum or white gold, the warm tones may appear somewhat more distinct.