It was purely by coincidence that my 2003 Onyx Green PT Cruiser became known as "Esmerelda". I was searching for something unique to call her, when my husband began calling her by that name. Somehow, it seemed to fit and she's been known by that since!

The name, Esmerelda, is of Spanish origin, translating into English as "emerald". Being curious, I sought out information about emeralds and their history...

The mining of emeralds has been dated back more than 3,000 years to the time of the Egyptian Empire. Until 1545, when the Conquistadors captured the Columbian mines, it was believed that the only sources of emeralds in the Ancient World were the Egyptian mines (known today as Cleopatra's Mines) exploited by the Pharaohs (from 3000 to 1500 B.C.) and those of Habatchal (Austria), captured by the Celts. However, the study of an old emerald in a Gallo-Roman earring reveals its origin to be the mines in the Swat Valley (Pakistan). Therefore, it appears that certain emeralds traded in Antiquity may also have come from the wealthy kingdoms which were located in what is today Pakistan and Afghanistan, along the silk route going through the Peshawar, Swat, and Kabul valleys.

The "green fire" was highly valued and so mesmerizing among the royalty of Europe that Spanish Conquistadors embarked on what would prove to be a bloody campaign to find the location of the emerald mines in South America.

When the Conquistadors landed in what is today Colombia, they found an abundance of these precious gems of a much better quality than those which had been quarried in Egypt. The Chibcha Indians who employed emeralds in religious offerings, personal adornment and trade, had mined these stones long before the Spanish conquest. The sight of so many emeralds among the natives aroused the greed of the Conquistadors.

Seeing the appetite of the Spaniards for gold, silver and precious stones, the Indians covered their mines and never revealed them to their conquerors. They hid them so well that even today, only two of their quarry sites, the spectacular Muzo and Chivor mines, have been discovered. Within a few years, they had relieved the Indians and their temples of these precious stones. They then enslaved the natives and forced them to mine emeralds on a large scale.

By the time that the Americas were discovered, the Egyptian emerald mines had been exhausted. However, after the Spanish conquest of South America, emeralds were to become much more common than in the previous centuries.

Emeralds are made of the base mineral beryl, with minute traces of chromium and vanadium which give the gemstone the appearance of "green fire." A good emerald is worth more than a same weight diamond. The Pope's ring carries this legendary gem and, in the past, the crowns of Persia and a good number of India's rajahs were adorned with the largest of these gemstones.

Of all the precious stones, emeralds are the only ones accepted with internal inclusions (imperfections). These faults indicate that the stones are natural rather than man-made. Stones that are black spotted, cloudy, milky, opaque or translucent are generally the least valuable. Large flawless stones are a rarity and the most valuable of all gems. The rough stones are usually found in veins of calcite – a dark-coloured carbon bearing limestone. Most are flawed hexagonal prisms, rarely exceeding 5 cm (2 in).

The best colour is an intense medium-dark, moss-grass green. The brilliance and sparkle of the stone is also important, compensating, at times, for light colour.

The production of artificial emeralds is relatively new. The first synthetic emerald was produced in 1935 by Carroll Chatham in his California laboratory. In the ensuing years, there has been large demand for these man-made stones, selling at about a tenth of the price of a real emerald.

Since the times of the Pharaohs, emeralds have been employed in folk medicine, through the centuries becoming the base of folklore and legends. Ancient Egyptians were the first to imbue them with magical powers – for women they became a symbol of desire, fertility and joy.

In India, which imported the stones from Egypt, a wealth of lore is attributed to them in Sanskrit sources. The Indians believed that emeralds were effective in warding off evil, misery and ill-fortune; keeping the body healthy; in the treatment of poisons and snake bites; and in the washing away of sin.

Egyptian and Indian lore about emeralds spread to ancient Greece, Rome and among the early Christians. Caesar wore an emerald around his neck to prevent epileptic fits and, according to the Bible, the emerald is the "4th stone" assigned to the 4th apostle, John the Evangelist, and as the 4th foundation stone of Jerusalem.

The emerald entered Western folklore through Spain in a substantial way after the Arabs conquered the Iberian Peninsula. In the subsequent centuries, its lore spread to the remainder of medieval Europe. In his book, Emerald and the Other Beryls, John Sinkankas attributes over a hundred occult properties to this gem.

The Emerald is the birthstone for May (the star sign Taurus), the gem for celebrating 55 years of marriage and the talisman for Mondays and the second hour of each day. Characteristics attributed to the Emerald are faith, courage, foresight and success in love.