C. 1980 Vintage 9.90 ct. t.w. Multi-Gemstone Cluster Earrings in 18kt Yellow Gold

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.

POST/CLUTCH: An earring with a post insert and a slide-on clutch backing to hold it in place.

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.

OVAL: An elliptical shape that resembles an egg.

CITRINE: A member of the quartz family, citrine symbolizes cheerfulness and prosperity. Its name is derived from the French word citron meaning lemon. This sunny stone comes in colors from lemon yellow to amber brown, with its coloring agent attributed to iron. Citrine is the birthstone for November.

TOPAZ: Available in a stunning selection of shades, the topaz's sky blue hue is one of the most popular colors for jewelry designs. Once thought to offer protection, today topaz is favored for its durability and affordability. Yellow topaz is the birthstone for November while blue topaz is for December.

AMETHYST: A natural variety of quartz, amethyst ranges in color from deep purple to pale lavender, and even to warm greens. Amethyst has been used during meditation to provide a sense of spiritual balance. Amethyst is the birthstone of February.

GARNET: the birthstone of January. One glance at the deep red seeds nestled inside of a pomegranate explains why the word "garnet" comes from the Latin word "granatus," meaning "grain" or "seed." This name was given to the garnet because of its close resemblance to the succulent seed.