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Varieties of Gemstones




Varieties of gemstones that are known all over the world....





Opal

opals Australia is the country of origin of Opals. Nature’s splendour seems to be reflected in the manifold opulence of these fine Opals. Ninety-five per cent almost of all fine opals come from the dry and remote deserts.

Many tales and legends about this colorful gemstone. It can be traced back in its origins to a time long ago. During the ancient times of the Australian aborigines. It is reported in their legends that the creator came down to Earth on a rainbow, in order to bring the message of peace to all the humans. And at the very spot, where his foot touched the ground, the stones became alive and started sparkling in all the colors of the rainbow. That was the origin of the Opals.

The group of fine Opals includes quite a number of wonderful gemstones, which share one characteristic: they shine and sparkle in a continually changing play of colors full of fantasy, which experts describe as “opalising”. Depending on the kind, place of occurrence, and color of the main body, we differentiate Dark or Black Opal, White or Light Opal, Milk or Crystal Opal, Boulder Opal, Opal Matrix, Yowah Nuts from Queensland – the so-called “picture stones“, and also Mexican and Fire Opal. Opal variations are practically unlimited. They all show in their own special way that unique play of colors – except for Fire Opal, which due to its transparency, however, is nevertheless also considered a Fine Opal specimen. If Opals are lacking the typical play of colors, they are simply named “Common Opal”.


Garnet

By the term 'garnet', the specialist understands a group of more than ten different gemstones of similar chemical composition. It is true to say that red is the color most often encountered, but the garnet also exists in various shades of green, a tender to intense yellow, a fiery orange and some fine earth-colored nuances. The only color it cannot offer is blue. Garnets are much sought-after and much worked gemstones - the more so because today it is not only the classical gemstone colors red and green which are so highly esteemed, but also the fine hues in between. Furthermore, the world of the garnets is also rich in rarities such as star garnets and stones whose color changes depending on whether they are seen in daylight or artificial light.

Why this gemstone is distinguishes on group from the others? Well, first of all there is its good hardness of 7 to 7.5 on the Mohs scale. With a few minor exceptions it applies to all the members of the garnet group, and it is the reason for the excellent wearing qualities of these gemstones. Garnets are relatively insensitive and uncomplicated to work with. The only thing they really don't like is being knocked about or subjected to improper heat treatment. A further plus is their high refractive index, the cause of the garnet's great brilliance. The shape of the raw crystals is also interesting. Garnet means something like 'the grainy one', coming from the Latin 'granum', for grain. This makes reference not only to the typical roundish shape of the crystals, but also to the color of the red garnet, which often puts one in mind of the seeds of a ripe pomegranate. In the Middle Ages, the red garnet was also called the 'carbuncle stone'.


Aquamarine

From light blue of the sky to the deep blue of the sea, aquamarines shine over extraordinarily beautiful range of mainly light blue colors. Aquamarine is a fascinating kind of gemstone. Women the world over love it for its fine blue shades which can complement almost any skin or eye color, and creative gemstone designers are inspired by it as they are by hardly any other gem, which enables them to create new artistic cuts again and again.

Its light blue arouses feelings of sympathy, trust, harmony and friendship. Good feelings. Feelings which are based on mutuality and which prove their worth in lasting relationships. The blue of aquamarine is a divine, eternal color, because it is the color of the sky. However, aquamarine blue is also the color of water with its life-giving force. And aquamarine really does seem to have captured the lucid blue of the oceans. No wonder, when you consider that according to the saga it originated in the treasure chest of fabulous mermaids, and has, since ancient times, been regarded as the sailors' lucky stone. Its name is derived from the Latin 'aqua' (water) and 'mare' (sea). It is said that its strengths are developed to their best advantage when it is placed in water which is bathed in sunlight. However, it is surely better still to wear aquamarine, since according to the old traditions this promises a happy marriage and is said to bring the woman who wears it joy and wealth into the bargain. An ideal gem, not only for loving and married couples.

Peridot

The vivid green of the peridot, with just a slight hint of gold, is the ideal gemstone color to go with that light summer wardrobe. No wonder – since the peridot is the gemstone of the summer month of August.

The peridot is a very old gemstone, and one which has become very popular again today. It is so ancient that it can be found in Egyptian jewellery from the early 2nd millennium B.C.. The stones used at that time came from a deposit on a small volcanic island in the Red Sea, some 45 miles off the Egyptian coast at Aswan, which was not rediscovered until about 1900 and has, meanwhile, been exhausted for quite some time. Having said that, the peridot is also a thoroughly modern gemstone, for it was not until a few years ago that peridot deposits were located in the Kashmir region; and the stones from those deposits, being of an incomparably beautiful color and transparency, have succeeded in giving a good polish to the image of this beautiful gemstone, which had paled somewhat over the millennia.

The ancient Romans too were fond of this gemstone and esteemed its radiant green shine, which does not change even in artificial light. For that reason they nicknamed it the 'emerald of the evening'. Peridot is also found in Europe in medieval churches, where it adorns many a treasure, for example one of the shrines in Cologne Cathedral. During the baroque period, the rich green gemstone once again enjoyed a brief heyday, and then it somehow faded into oblivion.

Citrine

That's roughly how things go with the citrine, the stone for the month of November. Many people have come to know and love this stone under the name gold topaz, or Madeira or Spanish topaz, although in actual fact it has very little in common with the higher-quality gemstone topaz - except for a few nuances of color. Thus the history of the citrine is closely interwoven with that of the topaz, and coincides with it completely when it comes to the interpretation of alleged miraculous powers. However, the citrine is a member of the large quartz family, a family which, with its multitude of colors and very various structures, offers gemstone lovers almost everything their hearts desire in terms of adornment and decoration, from absolutely clear rock crystal to black onyx. And it does so at prices which are by no means unaffordable.

The name is derived from the color - the yellow of the lemon - , although the most sought-after stones have a clear, radiant yellowish to brownish red. Like all crystal quartzes, the citrine has a hardness of 7 on the Mohs scale and is thus, to a large extent, insensitive to scratches. It won't immediately take offence at being knocked about either, since its cleavage properties are non-existent. Even if their refractive index is relatively low, the yellow stones have just that mellow, warm tone that seems to have captured the last glow of autumn. Like golden Rhine wine or sparkling Madeira, heavy and sweet, citrine jewellery shimmers and brings a hint of sunshine to those dull November days.

There are not many yellow gemstones in the world of jewels. A diamond or a sapphire may be yellow - those will be expensive -, or sometimes a tourmaline or chrysoberyl, though these tend toward green somewhat, a golden beryl or eben a pure topaz, which we will mention again later on. However, the citrine fulfils everyone's color wishes, from lemon yellow to reddish brown.

Rare though it is, yellow does in fact occur in quartz in Nature, if seldom, when there are traces of iron in the silicon dioxide. Historically, it has been found in Spain, on the Scottish island of Arran, in France, Hungary and in several mines overseas. Perhaps the citrine wouldn't have been talked about any more at all if, in the middle of the 18th century, it had not been for the discovery that amethysts and smoky quartzes can also be rendered yellow by so-called burning. This heat treatment at temperatures of between 470 and 560 degrees has to be carried out very carefully and requires a great deal of experience. However, in the course of 200 years, its application has become so much a matter of course that most of the stones available in the trade today are in fact burnt amethysts or smoky quartzes. Only a trained specialist can recognise the signs of heat treatment at all, burnt stones having subtle stripes whilst the yellow of natural ones is cloudy.

In Europe, the boom on these yellow to reddish crystal quartzes didn't begin until, in the 1930s, expatriate agate cutters from Idar-Oberstein sent large quantities of citrine back home, along with amethyst and agate, from Brazil and Uruguay. Thus the golden-yellow quartzes made a contribution to Idar-Oberstein's becoming - and remaining - one of the world's great gemstone centres. Just as they had been used to doing with agate and other kinds of quartz, the cutters faceted the citrine using large, rotating sandstones over decades. The raw stone was actually held in the cutter's hand during this process. If you give that a little thought, it will occur to you just how skilled the cutters from the Hunsrück really were.

Amethyst

Its color is as unique as it is seductive, though in fact this gemstone of all gemstones is said to protect its wearer against seduction. The amethyst is extravagance in violet. For many thousands of years, the most striking representative of the quartz family has been a jewel coveted by princes both ecclesiastical and secular. Moses described it as a symbol of the Spirit of God in the official robes of the High Priest of the Jews, and the Russian Empress Catherine the Great sent thousands of miners into the Urals to look for it. In popular belief, the amethyst offers protection against drunkenness - for the Greek words 'amethystos' mean 'not intoxicated' in translation. A more apt stone for the month of February, particularly if there is to be plenty going on in the way of carnival celebrations, could thus hardly be wished for.

A large number of further miraculous powers are attributed to the amethyst in all sorts of cultures. It was said to protect crops against tempests and locusts, bring good fortune in war and in the hunt, drive out evil spirits and inspire the intellect. A little study of the works of Pliny will reveal that this gemstone, if worn round the neck on a cord made from dog's hair, affords protection against snakebite. Later, Hieronymus even reported that eagles placed an amethyst in their nest in order to protect their young from the selfsame danger. Apart from these powers, gemstone therapists say that the amethyst has a sobering and cleansing effect. Amethyst has also been said to quell excessive stomach acid and, according to Hildegard von Bingen, served to combat insect bites and beautify the skin. But the amethyst not only had a firm niche in medicine; it was also esteemed as a stone of friendship. And since it was thought to put the wearer in a chaste frame of mind and symbolise trust and piety, the amethyst came to occupy a very prominent position in the ornaments of the Catholic clergy over the centuries. It was the stone of bishops and cardinals; we find it in prelates' crosses and in the so-called Papal Ring (Italian, 15th century) in the Jewellery Museum in Pforzheim.

However, the most beautiful of all crystal quartzes also posed one or two riddles for the scientists, and indeed they still haven't been completely solved to this day. The amethyst has its hardness (7), its moderate refraction and its weight in common with the other quartzes, but the crystal structure is different, and it is most unconventional. The construction is stratified, as a result of which areas and lamellae of varying color intensity often come about. This explains why there are relatively few large cut amethysts of an evenly distributed dark color, in spite of its having been found so abundantly in all parts of the world. It is only in the last few years that scientists have been fairly certain of having found the real cause of the color. It is now attributed to certain iron constituents in connection with natural radioactive radiation.

Sapphire


In earlier times, some people believed that the firmament was an enormous blue sapphire in which the Earth was embedded. Could there be a more apt image to describe the beauty of an immaculate sapphire? And yet this gem comes not in one but in all the blue shades of that firmament, from the deep blue of the evening sky to the shining mid-blue of a lovely summer's day which casts its spell over us. However, this magnificent gemstone also comes in many other colors: not only in the transparent greyish-blue of a distant horizon but also in the gloriously colorful play of light in a sunset – in yellow, pink, orange and purple. Sapphires really are gems of the sky, although they are found in the hard ground of our 'blue planet'.

Blue is the main color of the sapphire. Blue is also the favorite color of some 50 per cent of all people, men and women alike. We associate this color, strongly linked to the sapphire as it is, with feelings of sympathy and harmony, friendship and loyalty: feelings which belong to qualities that prove their worth in the long term – feelings in which it is not so much effervescent passion that is to the fore, but rather composure, mutual understanding and indestructible trust. Thus the blue of the sapphire has become a color which fits in with everything that is constant and reliable. That is one of the reasons why women in many countries wish for a sapphire ring on their engagement. The sapphire symbolizes loyalty, but at the same time it gives expression to people's love and longing. Perhaps the most famous example of this blue is to be found in music, in George Gershwin's "Rhapsody in Blue". And the blue of the sapphire even appears where nothing at all counts except clear-sightedness and concentrated mental effort. The first computer which succeeded in defeating a world chess champion bore the remarkable name 'Deep Blue'.


Ruby

Ruby is the red variety of the mineral corundum, one of the hardest minerals on Earth, of which the sapphire is also a variety. Pure corundum is colorless. Slight traces of elements such as chrome, iron, titanium or vanadium are responsible for the color. These gemstones have excellent hardness. On the Mohs scale their score of 9 is second only to that of the diamond. Only red corundum is entitled to be called ruby, all other colors being classified as sapphires. The close relationship between the ruby and the sapphire has only been known since the beginning of the 19th century. Up to that time, red garnets or spinels were also thought to be rubies. (That, indeed, is why the 'Black Ruby' and the 'Timur Ruby', two of the British Crown Jewels, were so named, when they are not actually rubies at all, but spinels.)

Ruby, this magnificent red variety from the multi-colored corundum family, consists of aluminium oxide and chrome as well as very fine traces of other elements - depending on which deposit it was from. In really fine colors and good clarity, however, this gemstone occurs only very rarely in the world's mines. Somewhat paradoxically, it is actually the coloring element chrome which is responsible for this scarcity. True enough, millions of years ago, when the gemstones were being created deep inside the core of the Earth, chrome was the element which gave the ruby its wonderful color. But at the same time it was also responsible for causing a multitude of fissures and cracks inside the crystals. Thus only very few ruby crystals were given the good conditions in which they could grow undisturbed to considerable sizes and crystallise to form perfect gemstones. For this reason, rubies of more than 3 carats in size are very rare. So it is no wonder that rubies with hardly any inclusions are so valuable that in good colors and larger sizes they achieve top prices at auctions, surpassing even those paid for diamonds in the same category.

For thousands of years, the ruby has been considered one of the most valuable gemstones on Earth. It has everything a precious stone should have: magnificent color, excellent hardness and outstanding brilliance. In addition to that, it is an extremely rare gemstone, especially in its finer qualities.

For a long time India was regarded as the ruby's classical country of origin. In the major works of Indian literature, a rich store of knowledge about gemstones has been handed down over a period of more than two thousand years. The term 'corundum', which we use today, is derived from the Sanskrit word 'kuruvinda'. The Sanskrit word for ruby is 'ratnaraj', which means something like 'king of the gemstones'. And it was a royal welcome indeed which used to be prepared for it. Whenever a particularly beautiful ruby crystal was found, the ruler sent high dignitaries out to meet the precious gemstone and welcome it in appropriate style. Today, rubies still decorate the insignia of many royal households.



Emerald
Emeralds are fascinating gemstones. They have the most beautiful, most intense and most radiant green that can possibly be imagined: emerald green. Inclusions are tolerated. In top quality, fine emeralds are even more valuable than diamonds.

The name emerald comes from the Greek 'smaragdos' via the Old French 'esmeralde', and really just means 'green gemstone'. Innumerable fantastic stories have grown up around this magnificent gem. The Incas and Aztecs of South America, where the best emeralds are still found today, regarded the emerald as a holy gemstone. However, probably the oldest known finds were once made near the Red Sea in Egypt. Having said that, these gemstone mines, already exploited by Egyptian pharaohs between 3000 and 1500 B.C. and later referred to as 'Cleopatra's Mines', had already been exhausted by the time they were rediscovered in the early 19th century.

Written many centuries ago, the Vedas, the holy scriptures of the Indians, say of the precious green gems and their healing properties: 'Emeralds promise good luck ...'; and 'The emerald enhances the well-being ...'. So it was no wonder that the treasure chests of Indian maharajas and maharanis contained wonderful emeralds. One of the world's largest is the so-called 'Mogul Emerald'. It dates from 1695, weighs 217.80 carats, and is some 10cm tall. One side of it is inscribed with prayer texts, and engraved on the other there are magnificent floral ornaments. This legendary emerald was auctioned by Christie's of London to an unidentified buyer for 2.2m US Dollars on September 28th 2001.

Emeralds have been held in high esteem since ancient times. For that reason, some of the most famous emeralds are to be seen in museums and collections. The New York Museum of Natural History, for example, has an exhibit in which a cup made of pure emerald which belonged to the Emperor Jehangir is shown next to the 'Patricia', one of the largest Colombian emerald crystals, which weighs 632 carats. The collection of the Bank of Bogota includes five valuable emerald crystals with weights of between 220 and 1796 carats, and splendid emeralds also form part of the Iranian National Treasury, adorning, for example, the diadem of the former Empress Farah. The Turkish sultans also loved emeralds. In Istanbul's Topkapi Palace there are exhibits with items of jewellery, writing-implements and daggers, each lavishly adorned with emeralds and other gems.


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