The Emerald the Most Costly of Precious Stones - Defective Stones - How Emeralds are Imitated - How to Test an Emerald - Some Famous Stones and their Owners - Mining for Emeralds Tourmalines - Peridots - Chrysoberyls
Jewels fluctuate in value, and an emerald is now the most costly of all precious stones. A fine emerald is worth from 8o to ioo per carat. A ruby of the same quality costs from £50 to ,60 per carat, and a good diamond is priced at about 30 per carat.
Emeralds are fragile, and ha\e not the adamantine qualities of the diamond, ruby, and Oriental sapphire. In fact, in the table of hardness they come after the topaz, but precede the amethyst and turquoise.
Emerald is the name given to a beryl of a pure, intense green colour. And the finest stones show a soft, velvety shade that delights the eye of an artist. Various opinions exist as to the source of the colour of an emerald. Some experts declare that it owes its beauty to the chrome which it contains, but the true secret seems as yet undiscovered. This precious gem has, however, several defects. There is, perhaps, no stone which suffers more from inequality of colour, structure, and transparency. It often has spots and cloudy patches, and is rendered dull by cracks and fissures which are described as " mossy." And it has yet another great drawback; it can be imitated with fatal facility.
Certain green minerals are sometimes substituted for emeralds. They include green garnets, green tourmalines, and sometimes chrysolite. These stones are, of course, genuine, but their value is not to be compared to that of the emerald.
A word may now be said on the subject of clever imitations. The process of making sham jewels is much as follows. Precious stones, such as emeralds, diamonds, rubies, and sapphires, can be imitated by means of a soft, heavy, flint-like glass, called strass, or paste, which is coloured by metallic oxides - red, blue, green and yellow - to imitate the stone required.
It must not be supposed that such pastes can be produced at small expense. The production of a strass suitable for making good imitations of real gems is a most complicated process. Hence only the most costly precious stones are imitated in this accurate manner.
Imitation stones can also be made by cementing thin plates of a precious substance over and sometimes under a body of common glass. In this case the exposed surface or surfaces when tested are found to be real stones, and the veneered mass passes as a genuine article of great value
But the best of all imitations are what are known as reconstructed stones, usually emeralds, rubies, or sapphires. These are made from chips of the real stone, found in mines, or else from cuttings, which are fused together, and the jewels thus made are cut in the ordinary manner. These are, in a sense, not frauds, as they have been formed of real stone, but are imitations that will deceive e\en a practised eye.
Experts declare that the art of copying precious gems fails in one point - namely, hardness. Practically all sham stones can be detected by their softness; they yield to the file, and may be scratched even by a bit of common glass An imitation stone, too, tarnishes in impure air, and is always heavier than the genuine article.
An emerald can be tested as follows. If the stone is real, the file will glide over it, but if false, the file will make lines and dents on its soft substance. The instrument must, however, be used with care, as a file too roughly handled might injure even a real emerald.
Emeralds are usually cut as brilliants, but a cabochon-cut emerald may have an effect that is rich, quiet, and beautiful.
It will be interesting here to add a few words on the subject of precious stones cut en cabochon.
There are several varieties of this sort of cutting. Opaque stones, such as the opal, moonstone, and turquoise, are commonly cut in this style. The one transparent stone which is often cabochon-cut is the garnet, and if a large garnet is cut in the hollow style it is then called a carbuncle. Although the cabochon form is almost essential to some precious stones, and is useful to hide the flaws and defects of others, connoisseurs declare that it ought not to displace the faceted form, which gives a far more brilliant effect.
In Europe fine emeralds are by no means common. The most precious are said to belong to the King of Saxony, and to be worthy of ranking with the unsurpassed rubies of the Court of Austria. Queen Mary and Queen Alexandra have also splendid stones; and Queen Maud of Norway owns a flexible waistbelt formed of one hundred fine emeralds and diamonds. These stones were given her at the time of her marriage by her Royal grandmother, the late Queen Victoria. Glorious emeralds are worn also by a few well-known women in society. The Duchess of Teck has some fine stones, which were a marriage gift from her father, the late Duke of Westminster. The Duchess of Buccleuch's emeralds are priceless, and the splendour of the square-cut emerald which, on great occasions, she wears on her breast is almost unrivalled.
A magnificent emerald and diamond ornament. Really fine emeralds are comparatively rarely seen in Europe, and are far more valuable than diamonds
The Duke of Norfolk owns two large, roughly cut emeralds set as hairpins. These are of historic interest, as they once belonged to Mary Queen of Scots. The Countess of Aberdeen has a high diamond crown, set with five huge emeralds, said to be the largest in the world, which was given her by her father the first Lord Tweedmouth. The Countess of Ilchester owns an emerald and diamond necklace of great price, which was a present on her marriage from her father, the Marquis of Londonderry. This is of emerald and diamond flowers, strung together with diamond chains, with a pendant of an enormous emerald surrounded by brilliants.