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Posts Tagged ‘colour’

Ruby-red means passion

April 16th, 2010

Red for ruby. Ruby-red. The most important thing about this precious stone is its colour. It was not for no reason that the name ‘ruby’ was derived from the Latin word ‘rubens’, meaning ‘red’. The red of the ruby is incomparable: warm and fiery. Two magical elements are associated with the symbolism of this colour: fire and blood, implying warmth and life for mankind. So ruby-red is not just any old colour, no, it is absolutely undiluted, hot, passionate, powerful colour. Like no other gemstone, the ruby is the perfect way to express powerful feelings. Instead of symbolising a calm, controlled affection, a ring set with a precious ruby bears witness to that passionate, unbridled love that people can feel for each other.

Colour above (almost) everything

As we have said, colour is a ruby’s most important feature. Its transparency is only of secondary importance. So inclusions do not impair the quality of a ruby unless they decrease the transparency of the stone or are located right in the centre of its table. On the contrary: inclusions within a ruby could be said to be its ‘fingerprint’, a statement of its individuality and, at the same time, proof of its genuineness and natural origin. The cut is essential: only a perfect cut will underline the beauty of this valuable and precious stone in a way befitting the ‘king of the gemstones’. However, a really perfect ruby is as rare as perfect love. If you do come across it, it will cost a small fortune. But when you have found ‘your’ ruby, don’t hesitate: hang on to it

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Birthplaces of fine rubies

April 16th, 2010

Which is the most beautiful ruby-red? Good question. The red of a ruby may involve very different nuances depending on its origin. The range of those nuances is quite wide, and could perhaps be compared to hotel categories, from luxury accommodation down to a plain inn or hostel. For example, if the gemstone experts refer to a ‘Burmese ruby’, they are talking about the top luxury category. However, it does not necessarily follow that the stone is of Burmese origin. It is basically an indication of the fact that the colour of the ruby in question is that typically shown by stones from the famous deposits in Burma (now Myanmar): a rich, full red with a slightly bluish hue. The colour is sometimes referred to as ‘pigeon-blood-red’, but the term ‘Burmese colour’ is a more fitting description. A connoisseur will immediately associate this colour with the legendary ‘Mogok Stone Tract’ and the gemstone centre of Mogok in the North of Myanmar. Here, the country’s famous ruby deposits lie in a mountain valley surrounded by high peaks. Painstakingly, gemstones of an irresistible luminosity are brought to light in the ‘valley of the rubies’. Unfortunately, really fine qualities are quite rare even here. The colour of a Burmese ruby is regarded as exceptionally vivid. It is said to display its unique brilliance in any light, be it natural or artificial.

The journey to the world’s most important ruby deposits takes us further on to the small town of Mong Hsu in the North-East of Myanmar, where the most important ruby deposits of the nineties lie. Originally, it was believed that these rubies would hardly prove suitable for use in jewellery, since untreated Mong Hsu ruby crystals actually display two colours: a purple to black core and a bright red periphery. Only when it had been discovered that the dark core could be turned into deep red by means of heat treatment did rubies from Mong Hsu begin to find their way on to the jewellery market. Today, the Mong Hsu gemstone mines are still among the most important ruby suppliers. In the main, they offer heat-treated rubies in commercial qualities and sizes between 0.5 and 3 carats.

Ruby deposits also exist in neighbouring Vietnam, near the Chinese border. Rubies of Vietnamese origin generally display a slightly purplish hue. Rubies from Thailand, another classical supplier, however, often have a darker red which tends towards brown. This ‘Siamese colour’ – an elegantly muted deep red – is considered second in beauty only to the Burmese colour, and is especially popular in the USA. Ceylon rubies, which have now become very rare, are mainly light red, like ripe raspberries.

Other ruby deposits are located in Northern Pakistan in the Hunza Valley, Kashmir, Tadzhikistan, Laos, Nepal, and Afghanistan. But rubies are also produced in India, where deposits with relatively large crystals were discovered in the federal states of Mysore and Orissa. These crystals have many inclusions, but they are, nevertheless, eminently suited to being cut as beads or cabochons.

Lately, people have begun to talk about East Africa as a source of rubies. Straight after their discovery in the 1960s, rubies from Kenya and Tanzania surprised the experts by their beautiful, strong colour, which may vary from light to dark red. But in the African mines too, fine and clear rubies of good colour, purity and size are very rare. Usually the qualities mined are of a merely average quality.

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Ruby – Only a little bit of chrome …

April 16th, 2010

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 colourless. Slight traces of elements such as chrome, iron, titanium or vanadium are responsible for the colour. 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 colours 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-coloured 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 colours and good clarity, however, this gemstone occurs only very rarely in the world’s mines. Somewhat paradoxically, it is actually the colouring 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 colour. 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 colours and larger sizes they achieve top prices at auctions, surpassing even those paid for diamonds in the same category.

Some rubies display a wonderful silky shine, the so-called ‘silk’ of the ruby. This phenomenon is caused by very fine needles of rutile. And now and then one of the rare star rubies is found. Here too, the mineral rutile is involved: having formed a star-shaped deposit within the ruby, it causes a captivating light effect known by the experts as asterism. If rubies of this kind are cut as half-dome shaped cabochons, the result is a six-spoked star which seems to glide magically across the surface of the stone when the latter is moved. Star rubies are precious rarities. Their value depends on the beauty and attractiveness of the colour and, though only to a lesser extent, on their transparency. Fine star rubies, however, should always display rays which are fully formed all the way to the imaginary horizontal line which runs through the middle of the stone, and the star itself should be situated right in the centre.

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Turquoise

April 16th, 2010

The turquoise is ancient, yet again and again it finds itself back in fashion. Its shining sky blue is one of the most popular trend colours in the world of jewellery and fashion.

In many cultures of the Old and New Worlds, this gemstone has been esteemed for thousands of years as a holy stone, a bringer of good fortune or a talisman. It really does have the right to be called a ‘gemstone of the peoples’. The oldest evidence for this claim was found in Egypt, where grave furnishings with turquoise inlay were discovered, dating from approximately 3000 B.C.. In the ancient Persian kingdom, the sky-blue gemstones were earlier worn round the neck or wrist as protection against unnatural death. If they changed colour, the wearer was thought to have reason to fear the approach of doom. Meanwhile, it has been discovered that the turquoise certainly can change colour, but that this is not necessarily a sign of impending danger. The change can be caused by the light, or by a chemical reaction brought about by cosmetics, dust or the acidity of the skin.

Turquoise affords protection and joie de vivre

In earlier times, turquoises were even responsible for the material wellbeing of the wearer. The Persian scholar Al-Qazwini, for example, wrote: ‘The hand that wears a turquoise and seals with it will never see poverty.’ Turquoises were often worn on the turban, and often surrounded with pearls, in order to protect their wearer against the ‘evil eye’. As talismans, they adorned daggers, sabres and the bridles of horses. It was not until the time of the crusades that they came to Europe. Indeed it is from that period that the name ‘turquoise’ originates, meaning ‘Turkish’.

In South, Central and North America too, the turquoise has always occupied a very special position among gemstones. The Aztecs in Mexico, for example, used to decorate their ceremonial masks with this stone which was holy according to their beliefs. The Indians of North America, who still produce a good deal of traditional silver jewellery with turquoises today, believe that the sky-blue gemstone opens up a direct connection between the sky and the sea.

At all times and over the world, turquoises have been worn as natural protection against the powers of darkness. If in earlier times they preserved horse and rider from unexpected falls, they are regarded today as the protective stone of pilots, air crews and other occupational groups who are exposed to an especially high degree of risk.

In modern gemstone therapy, those suffering from depression are recommended to wear a turquoise or a chain with turquoise beads. The turquoise’ cheerful colour is said to endow reticent personalities with more confidence. It is also often given as a gift, a stone of friendship, for the turquoise is said to be responsible for faithfulness and constancy in relationships.

The blue comes from copper, the green from iron

Turquoise is a copper aluminium phosphate with a hardness of 6, i.e. considerably softer than quartz. In Nature, it occurs in the whole range of hues from sky blue to grey-green, and it is mostly found in places where there is a high concentration of copper in the soil. However, turquoise is only really turquoise in the very best quality; mostly, the colour is paler, or bluish-green or greenish. The blue colour is created by copper, the green by bivalent iron and a certain amount of chrome. Often, the material has veins or blotches running through it, which are brown, light grey or black depending on where it was found. These lively, more or less regular patterns are known as ‘turquoise matrix’. The crystals are microscopically small and can hardly ever be recognised with the naked eye. As a rule, turquoise occurs as a fillung in veins or crevices, or in the form of nuggets. The most well known deposits are in the USA, Mexico, Israel, Iran, Afghanistan and China. The most beautiful turquoises, in a splendid light blue, come from deposits in the north of Iran.

Turquoise is rarely faceted. Usually, it is cut into cabochons or beads, or into some more imaginative shape.

Wax makes turquoise more resistant

Being relatively soft, turquoises are sensitive. As the colour may pale when the stone has been worn for a long time, even high-quality stones today are treated with wax and subsequently hardened. This treatment makes the sensitive gemstone more resistant. In the trade, there are a large number of reasonably priced turquoises sealed with synthetic resin. They have a fresh colour and good durability. However, many of them are dipped in a colouring medium before being subjected to durability treatment – a process that must, according to the rules of the ICA, be drawn to the attention of the prospective purchaser. And there is also such a thing as a ‘reconstructed turquoise’, which is made from pulverised turquoise.

Because of their sensitivity, turquoises are almost always subjected to treatment of one kind or another, though this may take any of a number of different forms. For this reason, turquoises which have a good natural colour and are simply hardened with colourless wax or synthetic resin have a much higher value than stones whose colour has been ‘improved’. So it is more advisable to purchase valuable turquoise jewellery at a jeweller’s.

Heaven on Earth

The best quality turquoises are of a pure, radiant sky blue, a colour which is highly esteemed with or without its fine, regular matrix. The more strongly the colour tends toward green and the more blotchy and more irregular the matrix, the lower the estimate of the stone’s quality.

Turquoise should be protected from cosmetics, heat and bright light. It is not a gemstone to take with you when you go sunbathing. It is best to give it a clean from time to time with a soft cloth.

The colour of the turquoise makes us feel happy and cheerful, for in it the light blue of the sky and the stimulating green of the sea are combined. Indeed it is such an inimitable colour that we have coined a term specifically for it in our languages: turquoise. Anyone choosing a turquoise is sure to enjoy a piece of Heaven … on Earth.

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