C. 1990 Vintage Black Onyx and 2.55 Carat Pink Tourmaline Tassel Necklace with Diamonds in 18kt Yellow Gold. 21"

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.

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.

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

Color Grade G-H: Near-colorless

Clarity VS1-VS2: Very slightly included. Inclusions are observed with effort under 10x magnification, but can be characterized as minor.

TOURMALINE: the "gemstone of the rainbow" comes in a dizzying array of colors and is usually created from more than a dozen elements, making it perfect for jewelry. The most popular tourmaline is deep pink, and a true favorite is watermelon... a gem of green and pink together.

HEART: A shape that takes the form of a heart symbol, with two curved sections at the top and a point at the bottom.

ONYX: A favorite of the ancient Greeks and Romans, this gemstone adds a sophisticated shine to rings, necklaces, bracelets and earrings. A dyed form of chalcedony, onyx is most popularly found in black although it can be green, white or red, as well.