C. 1990. Vintage 2.90 ct. t.w. Blue and White Diamond Ring in 14kt Yellow Gold. Size 8

14KT: Karat (abbreviated kt or K) is a unit that indicates the purity of gold in the metal. 14kt is 58.33% gold. In the United States, 14K yellow gold is most favored and used in jewelry.

YELLOW GOLD: Gold is a precious metal with a natural yellow color. It is quite soft and often alloyed with other metals to increase its strength. The purity of the metal is indicated by a unit called a "karat," with 24kt having the highest percentage of natural gold.

Diamond: The hardest and most brilliant of all gemstones, a diamond can make the heart race with its pure and fiery spark. An ancient symbol of love, a diamond is the preferred gemstone for tokens of affection, such as rings, earrings, necklaces and bracelets. Diamond is the birthstone for April.

BAGUETTE: An elongated rectangle step-cut. Typically used for smaller diamonds, but can be found in other gemstone as well.

CLARITY SI1-SI2: Slightly Included. Inclusions are noticeable under 10x magnification.

SINGLE-CUT: A gemstone cutting technique that dates back to the 1300s. Still used today, the single-cut usually features 18 facets that go in one direction without crossing each other.

Color Grade H-I: Near-colorless

CLARITY SI2: Slightly Included. Inclusions are noticeable under 10x magnification.