C. 1970 Vintage Yellow Glass Marquise Ring in 18kt Yellow Gold. Size 7

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.

TEXTURED: A unique and varying finish with a tactile surface applied through various techniques, both by hand and with machinery.

GLASS: A delicate, translucent to transparent noncrystalline material made by fusing sand with other materials , such as soda and lime, and then cooling it quickly. Glass is used in anything from windows to drinkware. In jewelry, glass is used for ornamentation, to make doublets, and to simulate gemstones.

MARQUISE: An elliptical shape that comes to a point at the top and bottom. Sometimes referred to as a "navette."