Black Agate and Red Enamel Cardinal Earrings in Two-Tone Sterling Silver

STERLING SILVER: Also known as "Standard Silver," sterling silver is silver alloyed with other metals to increase the hardness and durability. Generally, sterling is 92.5% silver and 7.5% other metals. Some sterling silver jewelry is plated with 14kt-18kt gold and referred to as "vermeil," or "gold over sterling."

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.

GOLD OVER STERLING: Sometimes referred to as "vermeil," this metal is gold-plated sterling silver. It is one of the most desirable gold-plated metals and can come in 14kt-24kt yellow, white, or rose.

ENAMEL: Enamel is a glass-like colored coating which is applied or "painted" over the surface of a piece of metal, ceramic or glass. Enamel is made from powdered glass or an epoxy resin material.

CLIP/POST: An earring with a post insert and a clip mechanism to hold it in place. The post can be removed by a jeweler to convert the earrings to clip-on.

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.

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