Ebonite
Ebonite (also called vulcanite) is a hard, moldable, polished dark colored (ranging from brown to black) early rubber. Ebonite was produced by adding sulfur to vulcanized rubber. It was used for combs, ornaments, and buttons. Ebonite is sometimes confused with gutta percha.

Ebony
Ebony is a hard, dark, dense wood sometimes used in jewelry.

Edwardian Period
The Edwardian period (also known as the Belle Epoque) was the time of the reign of Edward VII of England (1901-1910). Edwardian jewelry is delicate and elegant. Edwardian designs frequently use bows and filagrees. Pearls and diamonds were also frequently used.

Eisenberg
The Eisenberg company creates beautiful, high-quality costume jewelry. It was founded by Jonas Eisenberg in Chicago, Illinois in 1942, and is still in business. Originally, they made dresses with ornate buttons (made by the Ora company), and expanded into the costume jewelry business. The brooch above is a classic sterling piece from the 1940's. Eisenberg marks include (script) E, Eisenberg Original, and Eisenberg Ice (current).

Eilat Stone
Eilat stone is only found in King Solomon's copper mines on the Red Sea, near Eilat, Israel. This opaque green mineral is composed of azurite, malachite, turquoise, and chrysocolla. The hardness of this copper-based stone varies. There are many variations on its spelling, including Eliat, Elat, and Ellat.

Electroplating
Electroplating (also called Galvanotechnics after its inventor, Luigi Galvani) is a process in which one metal is coated with another metal using electricity. In jewelry, inexpensive metals are frequently electroplated with more expensive metals, like gold (gold plating), copper (electrocoppering), rhodium (rhodanizing), chromium (chromium plating), or silver (silver plating). The thickness of the metal coat varies. Electrogilded coating is the thinnest (less than 0.000007 inches thick); gold-cased metals have a coating thicker that 0.000007 inches.

Electrum
Electrum is an amber-colored alloy of gold and silver that was used in ancient times. Electrum is also an alloy used in medieval times consisting of copper (50%), nickel (30%) and zinc (20%).

Elie Ruby
An Elie ruby is actually a pyrope garnet (and not a ruby at all).

Email
Email (French for enamel) is a method in which enamel is applied to metal. It can be applied in many different ways, including cloisonné, champlevé, and plique à jour.

Emboss
Embossing is a method of surface decoration in which a design is raised slightly above the surface. Sheets of metal, leather, and plastic can be embossed.

Emerald
Emeralds are a very hard, green precious stone (beryl, Be3Al2Si6O18, colored by chromium and some vanadium impurities). Flaws and cloudiness (called jardin) are very common in emeralds, so many emeralds are oiled, irradiatied,and dyed to improve their look. Synthetic emeralds (developed by Carroll Chatham in the 1930's) have fewer imperfections and are very hard to distinguish from natural emeralds. Emeralds belong the beryl group of stones which also includes aquamarines, morganite, and chrysoberyl). Emeralds have a hardness of 7-8 and a specific gravity of 2.6 - 2.8. Emerald (and all forms of beryl) have large, perfect, six-sided crystals. Emeralds were long thought to have healing powers, especially for eyesight. During the renaissance, emeralds were used as a test for friendship among the aristocracy; an emerald given to a friend would remain perfect as long as the friendsip endured.

Emerald cut
Emerald cut stones have a girdle that is rectangular with truncated corners. Emerald cuts are frequently used on emeralds and diamonds.

Emmons
Emmons Jewelers, Inc., of Newark, NY, is a costume jewelry company that was founded by Charles H. Stuart. Emmons produced high-quality pieces under the marks Emmons, and Emmolite (and later, the Sarah Coventry line). Emmons jewelry was only sold at home jewelry parties organized by an Emmons representatives. The Emmons mark was first used in March, 1949. The Emmolite mark (for pieces made from base metal) was first used in January, 1955. During the late 1950's, the Emmons company started using the Sarah Coventry name. Emmons costume jewelry is very collectible and can be difficult to find.

Enamel
Enamel is a glassy substance (powdered glass with colorants) fused onto metal using heat (see cloisonné, champlevé, guilloche, and plique à jour).

ENGRAVE
Engraving is a method of surface decoration in which a design is etched into the surface with a sharp tool.

Enhanced
Enhanced stones are stones that have been treated to improve their color, clarity, finish, strength, or other characteristics. Some common enhancements are heat-treatment, irradiation, coating the surface, filling cracks, oiling, surface diffusion (coating the surface then applying heat), bleaching, dyeing, etc.

ESPO
ESPO and ESPO-FLEX are the marks of Esposito Jewelry, Inc., a costume jewelry company located in Providence, Rhode Island, USA. These marks were first used in 1951.

Etched Finish
An etched finish on a metal's surface reduces the metal's reflectivity. It is done by using harsh chemicals to eat into the surface or by cutting into the surface using a sharp tool.

Eternity Ring
An eternity ring is a narrow ring with gemstones set all around it.

Etruscan Jewelry
Ancient Etruscan jewelry has intricate and beautiful designs; most is made of gold. The Etruscans employed a lot of delicate granulation (n which tiny beads of gold are soldered to the surface to form a pattern) and openwork filagree (in which filagree patterns are not applied over sheet metal). The Etruscans lived in Northern Italy for hundreds of years beginning in the late 8th century B.C.

Etui
An etui (also called a necessaire) is a tiny, decorative, cylindrical-shaped case that was often carried on a chatelaine. The etui was used to carry small "necessary" items like pencils, scissors, manicure set, or spectacles. The etui was first used in the 1720's.

Eugene
Eugene was a jewelry designer who worked for Miriam Haskell and later started his own company around 1950. Eugene pieces were produced until the 1960's. These pieces are often complex, having beads and pearls, rhinestones, or enamel work.

European Cut
The European cut (also known as the old European cut) is an old, round diamond cut that is similar to but less bright than the newer brilliant cut. The European cut has a very small table and heavy crown.

EverGreen Topaz
EverGreen (R) is a trademarked type of diffusion-treated topaz. This deep green stone is produced by heating a cut, colorless topaz with coloring chemicals (mineral oxides), resulting in a thin layer of green coating the outside of the stone.

Eyepin
An eyepin is a thin wire with a loop at one end; it is used for linking beads together.

Excelsior Diamond
The Excelsior is the second or third largest diamond (depending on whether or not the Braganza diamond was actually a diamond). This irregular-shaped blue-white diamond was roughly 995 carats. It was found in l893 by a worker at the De Beers mine at Jagersfontein, Orange Free State, South Africa. The Excelsior diamond was cut in 1904 by I.J. Asscher and Company of Amsterdam into 21 stones, including a 69.80-carat marquise, an 18-carat marquise stone (which was displayed at the l939 World's Fair by the De Beers company), and many other stones.