C. 1980 Vintage Red Jade Pendant Necklace in 14kt Yellow Gold. 18"

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.

SPRINGRING CLASP: Invented in the early 1900s this diminutive device is highly effective. It's a hollow circular metal fastener with a spring opening. This keeps the clasp closed.

JADE: Available in many nuances of green, plus black, red, brown and white, jade has been treasured for its beauty and strength since prehistoric times. Prized above all other gemstones in ancient China, jade jewelry continues to captivate with a Far East mystique.

PEAR: Similar to the outline of a pear fruit, this is a round shape that comes to a point on one side.

CABOCHON: A style of cutting gemstones to achieve a smooth, domed surface with an absence of facets.