ELECTROPLATE
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.

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 friendship endured.

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

ENAMEL
Enamel is a glassy substance (powdered glass with colorants) fused onto metal using heat (see cloisonn?, champlev?, guilloche, and plique ? jour).

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

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 a ring of gemstones.

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.

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