C. 1930 Vintage Pink Agate Cameo Pin/Pendant in 10kt Two-Tone Gold

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

TWO-TONE GOLD: Gold is a precious metal which is often alloyed with other metals to increase strength and create different colors. A two-tone gold piece includes two colors of gold: yellow, rose, white, or gunmetal-finished gold. The purity of the metal is indicated by a unit called a "karat," with 24kt having the highest percentage of natural gold.

REVOLVER: A safety that conceals the point of a pin and keeps it in place with a revolving lever mechanism.

HINGED: A bale with a hinge. The hinge allows the pendant to be placed on and taken off a chain easily and without sliding. Ideal for putting pendants on chains that have large clasps.

AGATE: a variety of chalcedony, agate covers a rainbow spectrum of colors from black and gray to brown, pink, blue and yellow. Agate can be textured and exhibit a variegated layered stripe effect, which makes it a wonderful stone for carved cameos and beaded necklaces and bracelets.

OVAL: An elliptical shape that resembles an egg.

CARVED: When a gemstone is cut so that the outline or surface takes the form or likeness of a specific image or pattern.