Emerald

Color:   Bluish green to vivid grass green to slightly yellowish green
   
Gem Family:   Emerald is a unique variety of the mineral beryl.
   
Source:   Emerald is mined in Colombia, Brazil, Zambia, Pakistan, Afghanistan, Zimbabwe, and Madagascar.
   
Clarity:   Almost always found with inclusions, tiny fissures and crystals that the French call the jardin, or garden, because they resemble foliage inside the gem.
   
Size Range:   0.5 carat to 3 carats. Larger sizes are increasingly rare and valuable.
   
Shapes Available:   Most commonly seen in the octagon step cut, more commonly known as the emerald cut. For extra brillance, some emeralds are cut in the barion or emerald brilliant cut, with adds more sparkle from extra facet reflections. Emeralds are also available in ovals, princess cuts, rounds, and trillions although other shapes are less common in large sizes.
   
Enhancement:   Virtually all emeralds have tiny fissures filled with oil, resin, or chemicals. Only a very few emeralds have no fissure filling whatsoever. If a jeweler tells you all his emeralds aren't enhanced, he probably isn't truthful! Traditional oil is the most preferred enhancement because it is reversible. New epoxy resins are durable but may be difficult to remove if damaged. Lower quality emeralds can be made to look better with epoxy resins.
   
Lore & History:   Treasured for 4,000 years, emerald is the essence of Spring, a symbol of rebirth prized by the ancients as the gem representing love and new life. Legend says emerald protects a marriage and increases fertility. The Ancient Romans associated emerald's powers with Venus, the Goddess of Love. Many seekers said the Holy Grail was carved from emerald.
   
Toughness & Hardness:   The hardness of emerald is 7.5 to 8 on the Mohs scale.
   
Care & Cleaning:   Although emerald is quite hard and durable, inclusions can weaken its crystal structure. Avoid sharp impacts on the stone and shapes with exposed points, like a marquise, should be protected. Clean with warm water, detergent, and a soft brush. Store separately from other jewelry and gemstones. Never put emerald in ultrasonic or steam cleaners.
   
Price Range:   $500 to $4,000 per carat for sizes from 0.25 to 1.00 carat. Gems between 1 to 3 carats can be as much as $10,000 per carat. Exceptional gems and larger sizes can be much more.
   
Special Characteristics:   Ancient emeralds were from mines in Egypt, now called Cleopatra's mines, since Cleopatra was famous for wearing emerald.  Egyptian Mummies were buried with an emerald to symbolize eternal life.  Today we would find Cleopatra's emeralds unimpressive.  Spanish explorers in the new world were staggered by the size, color, and quality of emeralds they saw when arriving in the New World.  They spent almost a century searching for the source, which they finally located in Colombia, the El Dorado of gems.