The emerald is probably the most rare of all precious stones and is considered by some to be even more valuable than the diamond. Compared with other precious stones the emerald in its occurrence in nature is unique, for it is found in the rock in which it was formed. Unlike diamonds, sapphires and rubies, it never occurs in gem gravels. The earliest known locality where emeralds were found was in Upper Egypt near the coast of the Red Sea. The best stones, however, are found in Columbia, South America. Fine specimens have also been found in the United States in North Carolina.

While the usual shade of color seen in emeralds is alluded to as emerald green, there are other shades, such as grass green, sea green and green slightly tinged with yellow. The shades most highly valued are those of an intense fresh green sometimes compared with that seen in a meadow in spring.

Beryl is a mineral known to gem lovers under several different names, the most valued of which is the Emerald. The mineral beryl composing the various gems is practically the same in composition, hardness, and other properties, and the gems may be differentiated only by their color. In composition beryl is a silicate of aluminum and glucinum. On the scale of hardness beryl is graded 7 to 8, and is thus much softer than the diamond, ruby, or sapphire. It is owing to this fact that the emerald scratches easily and that care must be taken that when worn it is not subject to chafing by diamonds or other harder gems.

Beryl as a mineral is of quite common occurrence, and the crystals of the mineral in its cruder form often grow to enormous size. There is one such single crystal preserved in the Boston Museum of Natural History, which is three and one half feet long and three feet wide and weighs several tons.

Beryl in this common form occurs in many localities, but the mineral in its rarer form of emerald is comparatively of very rare occurrence. The emerald or green beryl, as it should be scientifically known, has long been the most highly prized of the green gems. In brilliancy it exceeds all other green gems excepting only the very rare green sapphire. The most valuable specimens exhibit a vivid grass-green shade, and it is to this color that they owe their great value. Other considerations, such as freedom from imperfections, are quite secondary in determining the value of the stone. In fact a perfect emerald is almost never found, and this circumstance has passed into an Eastern simile which runs, As scarce as a perfect emerald, this being a symbol for the acme of rarity. The emerald is light in weight and an emerald of a given size will be about a third larger than a diamond and forty-five per cent larger than a sapphire of equal weight. The distinctive color of the emerald is probably due to a trace of chromium in its composition.

Fine emeralds are generally cut cushion shape with step cutting, and in the East are often cut cabochon. Fine emeralds have advanced very rapidly during the last few years, both on account of the growing demand of fashion for the gems and the scarcity of really fine specimens.

Many curious legends of gigantic emeralds have been handed down to us, principally culled from the narratives of early travelers, who thought every transparent green stone they saw to be an emerald.

The ancients valued the emerald highly, not alone for its beauty, but for its supposed occult properties and its marvelous power of healing all diseases of the eyethey also believed that if the eyes of a serpent met the gleam of the emerald, it immediately became blind. Moore alludes to this superstition in the lines:

Blinded like serpents when they gaze
Upon the emeralds virgin blaze.

The Emperor Nero, who was shortsighted, had an eye-glass formed of an emerald, through which he gazed and gloated over the cruel sports of the arena.

Many interesting stories are told of the first emeralds taken by the early conquerors of Peru to Spain, and a certain Joseph D Acosta is said to have returned to Spain in 1587 with two chests of emeralds, each of which weighed over one hundred pounds. The truth of this story may be questioned, but it is a fact that the stones were highly prized and much used by the Incas and Aztecs in the extraordinary civilization which once existed in Peru. The emerald was highly prized by the ancients and by gem lovers of the middle ages, and this accounts for many interesting legends and superstitions relating to the gem.

As for today, the emerald is still very highly valued as one of the most precious stones. The emerald is Mays birthstone and is a favorite stone for fine jewelry craftsmen throughout the world.