C. 1970 Vintage 8.25 Carat Smoky Quartz Ring in 14kt Yellow Gold. Size 5.5

14KT: Karat (abbreviated kt or K) is a unit that indicates the purity of gold in the metal. 14kt is 58.33% gold. In the United States, 14K 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.

QUARTZ: From the icy shimmer of rock crystal quartz to the delicate pink of rose quartz to the moody hues of smoky quartz, this gemstone offers something for everyone. Quartz, found in endless colors and varieties, is a popular choice for bracelets, necklaces, rings and earrings.

EMERALD: the birthstone of May, and from the beryl mineral family, the emerald has been a prized possession of royalty since ancient times and a good quality emerald can be as or even more expensive than a fine diamond of the same carat. Emeralds are considered the traditional gift for the 55th wedding anniversary.