May's birthstone is the emerald.  Emerald is the green version of the mineral Beryl.  It was considered to be the talisman of the goddess Venus, and to represent faith, goodness and kindness.
 
     Emeralds vary in color from light to deep green. It is commonly thought  that an emerald's green colour derives from the presence of chromium and  or vanadium replacing some of the aluminum in the mineral's structure.  The stone can, however, lose its color when heated strongly.
 

    The emerald's name is indirectly derived from the Greek word "smaragdos," a term ambiguously applied to several kinds of green stones. The history of emeralds can be traced  back to antiquity. They were worn by royalty in Babylon and Egypt. Tools dating back to 1300 B.C., during the reign of Rameses II, have been found in emerald mines in Egypt. Queen Cleopatra's emeralds were believed to originate from mines in Southern Egypt, near the Red Sea.
 
     Several famous historical artifacts were made of emeralds. Among them was the Crown of Andes, said to be worn by the last Inca king of Peru  who was taken prisoner by  Conquistador Pizzaro in 1532. The crown was said to be set with 453  emeralds, collectively weighing ten ounces (1523 carats). In the 1940s, the crown was sold to, then broken up  by, an American syndicate. Many of its stones are probably in the jewelry  collections of wealthy Americans today.

     The Holy Grail Cup at the Cathedral in Genoa, Italy is said to be over 700 years old. Legend has it that it was taken from King Herod's banquet table by the disciples to be used by Jesus at the Last Supper. In the twelfth century, Crusaders returning from the Holy Land  brought the Grail to Genoa.

     Emerald has been considered as a "medicinal" stone to soothe strained and tired eyes, just by gazing at a nice green one.  Engraved with the image of a frog, it is supposed to help restore peace  It is supposed by many to be good for preventing epileptic attacks, stopping bleeding and soothing fears and irritations. It was also believed that laying the emerald on the forehead would break a fever. In "gem elixirs" emerald is supposed to be good for all kinds of digestive problems.  It is also said to be of value in immune system deficiencies, and to improve meditation and psychic abilities.
Colombia in South America is the most famous and possibly the most important source for high-quality stones. Siberia (Russia), Brazil, and the Sandawana  area in Zimbabwe are known to have produced significant quantities of gems. In the U.S., North Carolina, especially the Spruce Pine area is the only significant source of emerald.

     Emeralds can range in price from quite cheap to incredibly expensive. Their quality too ranges from poor to sensational with a side warning about fakes. More so than any other gem, fake emeralds have popped up in the market.  These are excellent imitations made of colored cut glass. Too, synthetic emeralds have been around since the 1940's. While quite pretty, they do not carry much value. Should you decide to purchase an emerald, take someone with you who knows gemstones!