C. 1990 Vintage Bulgari .60 Carat Blue Topaz and .50 Carat Pink Tourmaline Heart Bypass Ring in 18kt Yellow Gold. Size 7.5

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.

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.

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

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.