C. 1990 1.75 Carat Blue Topaz and .10 ct. t.w. Purple Tanzanite in 10kt Yellow Gold. Size 7

10KT: Karat (abbreviated kt or K) is a unit that indicates the purity of gold in the metal. 10kt is 41.67% gold.

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.

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

TANZANITE: Found in the 1960's, tanzanite is new and rare discovery that captures magnificent shades of purple, violet and blue. Its crystal structure allows light to enter the stone and divide into two or three sectors which enhances the intensity of color. Tanzanite is an alternate for December birthstones.