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 Although gemstones are among the most durable of substances, they do need some care. Following a few general rules will make sure that they last for generations still looking like the day you bought them.
First of all: keep them clean! Rings in particular tend to collect dust and soap behind the stone, particularly if you wear them all the time. To clean transparent crystalline gemstones, simply soak them in water with a touch of gentle soap. If necessary, use a soft toothbrush to scrub behind the stone.
Even the hardest gemstone variety can be vulnerable to breakage if it has inclusions that weaken the crystal structure. Exercise common sense: if you have a ring set with a softer gem variety or an included stone, take it off before strenous exercise.
Diamonds are very hard but can shatter in two with a single well-placed blow. Rubies and sapphires are the toughest gems but even they can chip if hit sharply.
Think twice before putting gems in an ultrasonic cleaner. Diamonds and rubies and sapphires will be fine but many other gems may not be: when in doubt, leave it out. Diamonds, rubies and sapphires, and other single-crystal gems can be cleaned with a touch of ammonia in water to remove all films and add extra sparkle.
Opaque gemstones like lapis lazuli, turquoise, malachite, require special care. Never use an ultrasonic cleaner and never use ammonia or any chemical solution. These gem materials should just be wiped clean gently with a moist cloth. These gemstones can be porous and may absorb chemicals, even soap, and they may build up inside the stone and discolor it.
The reason why these materials need more care than transparent gemstones is that these materials are essentially rocks, not crystals of a single mineral. Think about it: when you put a rock in water, it absorbs the water and is moist all the way through. A single crystal gem like sapphire will not absorb water: all the molecules are lined up so tightly in the crystal that there is no room for water to enter.
Opals also require special care. Never use an ultrasonic, never use ammonia, and avoid heat and strong light which can dry out the water in opals.
Organic gems like pearls, coral, and amber should only be wiped clean with a moist cloth. Due to their organic nature, these gems are both soft and porous. Be careful about chemicals in hairspray, cosmetics, or perfume: they can, over time, damage pearls in particular.
Store each piece of gemstone jewelry separately so that harder stones don't scratch softer ones. Almost every gemstone is much harder than the metal it is set in. Gems can scratch the finish on your gold, silver or platinum if you throw your jewelry in a heap in a drawer or jewelry box.
 A 101.27 carat diamond the size of a squash ball will be sold by auction house Christie's in Hong Kong next month and is likely to fetch up to $7.5 million.The gem is the largest colourless diamond to show on the auction market in 18 years and one of only three colourless diamonds of over 100-carats to have ever been auctioned, Christie's said.
The gem, which is internally faultless but rated VVS1 (very very a little imperfect 1st degree) for simplicity is expected to fetch upwards of $6 million -- a relatively low per-carat price.A 39.34-carat "D" colour, flawless diamond sold for $6.87 million at a Christie's New York sale earlier this month. While rare sophisticated diamonds achieved all-time highs per carat at sales in Geneva late last year, a much-hyped 72.22 carat "D" flawless white diamond failed to sell at a Sotheby's Hong Kong auction earlier this month, suggesting demand for top stones may be waning due to a weakening world economy.
The 101-carat "shield-shape" stone was cut from a 460-carat hunk of rough precious stone and mounted on a tiara, rather than a choker or pendant given its extraordinary thickness.
"With Asia becoming such a vibrant market, it is fitting that this rarest gem should be offered ... to the growing number of collectors in the area," said Francois Curiel, Christie's chairman of jewellery, in a statement.
Naming rights for the gem will be granted to the buyer, who Christie's said might come from Russia or the Middle East.
Other items to feature in Christie's May 28 sale include a coloured diamond ring set with a fancy green diamond estimated to be worth $3 million, as well as a rare emerald and diamond ring set with a 14.31 carat emerald that could fetch $800,000.
 Star clusters can be held together tightly by gravity, as is the case with densely packed crowds of hundreds of thousands of stars, called globular clusters. Or, they can be more loosely bound, irregularly shaped groupings of up to several thousands of stars, like the open clusters shown in this image.
The stars in these open clusters are all relatively young and were born from the same cloud of interstellar gas. Just as old school-friends drift apart after graduation, the stars in an open cluster will only remain together for a limited time and gradually disperse into space, pulled away by the gravitational tugs of other passing clusters and clouds of gas. Most open clusters dissolve within a few hundred million years, whereas the more tightly bound globular clusters can exist for many billions of years.
Open star clusters make excellent astronomical laboratories. The stars may have different masses, but all are at about the same distance, move in the same general direction, and have approximately the same age and chemical composition. They can be studied and compared to find out more about stellar evolution, the ages of such clusters, and much more.
The Small Magellanic Cloud, which hosts the two star clusters, is one of the small satellite galaxies of the Milky Way. It can be seen with the unaided eye as a hazy patch in the constellation Tucana (the Toucan) in the Southern Hemisphere. The Small Magellanic Cloud is rich in gas nebulae and star clusters. It is most likely that this irregular galaxy has been disrupted through repeated interactions with the Milky Way, resulting in the vigorous star-forming activity seen throughout the cloud. NGC 265 and NGC 290 may very well owe their existence to these close encounters with the Milky Way.
 The cultured pearl industry has experienced a dramatic transformation during the past 15 years, from a single commodity dominated by one country to a multi-colored array of goods and an ever-expanding group of producers.
Japanese Dealers Relinquish Control
For many decades after pioneering the cultured pearl in the early twentieth century, Japanese companies maintained tight control over its technology, production and distribution (figure 2). In the 1960s, however, large, white South Sea cultured pearls from Australia and black cultured pearls from French Polynesia began entering the market alongside the traditional white Japanese akoya.
The French Polynesians initially struggled to gain acceptance for their products, as many believed they were treated-color. A breakthrough came in the early 1970s when GIA researcher Robert Crowningshield determined their black color was indeed natural. Meanwhile, the South Sea cultured pearl was becoming a branded fashion item, though the Australians still marketed their output solely through Japanese wholesalers.
The real changes began in the 1990s, when the nearly century-long grip of the Japanese loosened due to a combination of factors: aggressive marketing efforts for South Sea and black French Polynesian pearls; the rise of lower-cost, fine-quality Chinese freshwater cultured pearls
The Australians and the French Polynesians (now selling under the “Tahitian” banner) began marketing their products as distinct from Japanese akoyas: the South Sea goods as luxury items that were not subjected to treatments, the Tahitians as exotic fashion pieces. Producers of both types of cultured pearls embarked on multi-million-dollar consumer campaigns to promote their goods and the images they wanted them to convey.
 By the mid-1990s, Chinese farmers, who for years had produced small, irregularly shaped and very inexpensive goods (dubbed “rice krispie pearls”), were successfully growing round, akoya-like cultured pearls. The quantity of Chinese goods entering the market threatened to inundate Japanese distributors. The Japanese entered talks with the Chinese government in an effort to control production and exports of such goods, but they failed on both fronts. Then, in 1996, reports began filtering in that Japanese pearl farms were suffering the massive mortality of their oyster crops. By year’s end, an estimated two-thirds of the akoya oysters under cultivation in Japanese waters had died from infectious disease—a blow from which that country’s cultured pearl industry has not yet fully recovered. As a result, Japanese producers no longer had the financial resources to control supplies and distribution, thus creating a true free market within the industry.
The inhorgenta europe 2008, which took place on the grounds of the New Munich Trade Fair Centre from 15 to 18 February 2008, was able to confirm its role as one of the leading trade fairs in the industry. A total of 1,224 exhibitors (2007: 1,183) from 48 countries (2007: 44) exhibited at the 35th International Fair for Watches, Clocks, Jewellery, Precious Stones, Pearls and Technology this year.
The very high level of previous years was also maintained on the trade visitor side with more than 30,000 visitors from 78 countries. Thus, once again inhorgenta europe was able to demonstrate its international character with a foreign share of 32%. Greece, the Netherlands, Hungary and the Czech Republic had the highest growth rates. As a result, the trend of the past years has again been confirmed: an increasing number of trade visitors are attending from the up-and-coming markets in the East.
Manfred Wutzlhofer, Chief Executive Officer of Messe München GmbH: "In spite of the more difficult framework conditions compared to 2007, for example the increase of prices for precious metals, the majority of exhibitors at inhorgenta europe reported good business. This was certainly also supported by the high number of foreign trade visitors. We were able to record a substantial increase especially from Eastern Europe."
The positive overall course of the trade fair, the good ambience at inhorgenta europe 2008 and the grouping of the industry categories were especially emphasized in the TNS Infratest survey. Both inhorgenta europe management and exhibitors saw one reason for the positive assessment of this years arrangement of the fair in the pooling of the complete offer for precious stones and pearls in Hall C1. As a result, the trade fair did justice to the increased interest in this jewelry segment. This trade fair area enjoyed a correspondingly high degree of favor among visitors; 95% of the trade visitors assessed both the offer of precious stones and pearls as excellent to good.
Ph. Hahn Söhne, Dieter Hahn, Owner: "Contrary to the belief of all skeptics, inhorgenta europe 2008 proved that the centralisation of competency in precious stones in Hall C1 was a great success. It created easier orientation for trade visitors. Those in the know in the industry can speak on equal terms there. The positive tendency of last year continued in our business transactions. Nothing in the way of a downturn is noticeable."
Amber, which is actually fossilized pine sap, has become, through the creativity of men, part of jewelry. Amber jewelry is today more or less a part of our lives. The difference between now and decades ago is only one: everyone can afford a piece of amber jewelry today and doesn’t know what to do with it, but a long time ago people suspected its powers and a lot of them couldn’t afford to own this kind of jewelry.
The first name given to amber was electron. After that, around the sixth century B.C., the scientists of that time discovered that, if you rubbed amber against a wool cloth, it became electrically charged. Because of its property it could attract small pieces of paper, fact which amazed the people of that time. Carrying a negative electrical charge, it was thought that the stone itself was able to draw power and energy into its bearer. This belief helped make the stone famous and valuable. People started using it in amber jewelry and making amulets and magical objects. Besides being able to attract energy, it was believed that it aided the intellect. It was prescribed for a lot of curious illnesses like memory loss, anxiety and eccentric behavior.
Amber jewelry was known for its capacity to influence the mood of the bearer. People though that wearing amber jewelry would help them and that the small yellow-brown stone could lighten the burdens of their lives filling their spirit with white light. The results of its actions were supposes to be a feeling of happiness and joy. From the healer’s point of view, the idea was that amber jewelry somehow activated the altruistic side and made people realize the power of their spiritual intellect to the fullest.
For thousands of years amber has been regarded as a precious substance for its warm beauty. Because no one knew then were it came from, it was thought to be of divine origin. People believed that no harm could come to the one that wore amber jewelry because the stone would protect him. Because of these beliefs the stone become used for medical purposes. Philosophers and alchemists have tried for a long period of time to explain how the amber stones came to be and looked the way they did. Around the first century A.D. a Roman senator and historian recorded a popular belief on the forming of the stone. He wrote it was formed from the urine of the lynx. The male was supposed to produce the dark colored stones and the females the lighter ones with yellow colors. Since there was no explanation to how this miraculous gem appeared, people became superstitious. Another one of the spoken beliefs was that the rays of the setting sun were concealed in the evening sea and then they were cast upon the shore in the form of the stone we all know. This is why we can say that amber jewelry is a piece of brilliant sun. Around the year 240 B.C., an astrologer, Sudines, came pretty close to the real origin of amber. He said that the gemstone is the product of a tree called the “lynx”. It was indeed the product of a tree. Amber was a resin.
The one that made the amber color and amber jewelry famous was Nero. He compared his wife’s hair to the color of the gemstone. From that point on every respectable woman, wives of the noble men at that time, started to aspire to that color and it became a symbol. The woman with the red hair that had the setting sun reflected in the evening sea trapped in her hair felt very proud of the similitude between the amber stone and her beauty. That’s why amber jewelry is regarded the way it is. A small piece of “brilliant sun” or “frozen gold” hides the mysteries of the gem in the beauty of the amber jewelry.
As for the medical use of amber, nothing can be scientifically proven. The ancient Romans had great confidence in the powers of baltic amber jewelry and they used amber in other ways too. They thought that some powder of the gemstone taken in a cup of wine could cure illnesses like fever, asthma or even infections of the throat. This type of medicine was used by the ancient Romans for ear and eye problems too. A fine powder was mixed with honey and, sometimes, with oil made from roses and it was either poured on the infected area or taken internally. Not all types of amber were thought to have healing proprieties, only the reddish stones. Nowadays, it’s also recommended to wear some amber jewelry around the neck (a necklace or a pendant) for the same purpose.
Wearing amber jewelry is a double win situation: it looks good and makes you feel good also. Precious, mysterious and miraculous, amber is by far the most complex gemstone. Its past and its aspect still fascinate a lot of people. Amber jewelry can create an effect that no diamond can ever do and is indeed, as poets say, “a slice of sunshine”.
The colour impression made by a gemstone is dependent on a remarkable number of influencing factors. There is the nature of the light source, the colours of the surroundings and background, and then of course the ethnic disposition of the man or woman who wears the stone. In addition to that, the eye of the beholder with its own individual colour perception and age, as well as its own particular traditional aesthetic sensibilities all play a part, too.
So it is that this colour impression made on the gemstone lover will vary again and again at different times of the day and in different seasons, and this too lends a certain charm to our perception of it.
Comparison with Nature’s other coloured “gems” helps us to understand these interactions; for example the flowers in our garden, whose colour in the morning may appear to us quite different to their colour in the afternoon or evening. They are a delight to our eyes with the variety of their colour in the natural light of day, but also when used as decoration in artificial light.
In the flower shop, when they are arranged and presented to us, we are often astounded by the dramatic beauty of their colours, as we would be by an actor spotlighted on stage.
No-one would consider lighting that stage as you would an office. What makes an impression on the observer is good, accentuated light that brings out the best in its subject.
This applies to the gemstones of the world in a similar way. We don’t really come to appreciate their beauty until they are captured, like those actors on stage, in a beam of carefully trained light, such as LEDs, quartz halogens or full spectrum fluorescents. This in fact is the secret of the fascination held for diamonds. Its extremely high refraction means that it lights up even when there is only very little incident light, though it must be said that the perception of its body colour is more difficult, and affected by its cut and especially its size.
Coloured stones, on the other hand, have lower refraction, but as they are typically larger than diamonds, their colour presence leads to a more intense impression. Having said that, the cut, i.e. the surfaces by which the incident light is reflected and refracted, is of decisive importance. It opens our eyes to the colour universe of the gemstones. The cut is a window to the variety of those colours, which run across the whole spectrum of the rainbow; colours which, in their origin, lay hidden within the rough unpolished stone.
The impression made by a coloured gemstone and its sensation to the observer is influenced by a number of unique color attributes: hue, lightness (tone/value) and saturation of the colour (chroma/intensity), as well as dichroism and dispersion.
Together with the influencing factors already referred to, these determine how we actually perceive the gems and their colours.
On account of these many variables, gemstones have the ability to surprise us in different guises again and again.
Professionals who work in the world of gemstones, such as the members of the ICA, are by no means immune to this variability either. It is they who accompany the gem material on their long journey, from the moment they leave the mine, and get polished, up to the moment they become parts of jewellery. It is their highly unique abilities which ensure that the true value of gemstones is brought out and, when all is said and done, that the wearer can derive pure enjoyment from them. In view of the diversity already described and the rarity of the stones, this is thoroughly challenging work. Experience and integrity, and a background which in many cases goes back over several generations, mean that the world of coloured gems is quite different to that of diamonds or pearls.
Thus the right kind of light and the optimum cut supports each stone in its natural beauty, to the delight of the person who wears it and the ones who are admiring it.
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