C. 1990 Vintage 5.25 Carat Green Prasiolite and .75 ct. t.w. Diamond Ring in 18kt White Gold. Size 6

18KT: Karat (abbreviated kt or K) is a unit that indicates the purity of gold in the metal. 18kt is 75% gold. In Europe, 18K yellow gold is most favored and used in jewelry.

WHITE GOLD: Gold is a precious metal which is naturally quite soft. To give it a white color and increase its strength, gold is alloyed with white metals, such as silver and/or palladium, and often plated with rhodium. 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.

BRILLIANT: A gemstone cut to enhance brilliance without sacrificing much carat weight. Typically has 58 facets.

Color Grade H-I: Near-colorless

Clarity VS2: Very slightly included. Inclusions are observed with effort under 10x magnification, but can be characterized as minor.

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

PRASIOLITE: A warm- to yellow-green variety of quartz. It is a rare gemstone in nature and often the color comes from the process of heat treatment. It is sometimes referred to as green amethyst or lime citrine.