How to Judge the Quality of Your Gemstone’s Setting

Now that you have found the perfect gem, all you need to do is make sure it is displayed well and held securely in place.

To judge the quality of the jewelry setting, pay close attention to details. Is the metal holding the stone even and smoothly finished so it won't catch on clothing? Is the stone held firmly and square in the setting? Is the metal well polished with no little burrs of metal or pockmarks?

Inexpensive jewelry often is very lightweight to give you a bigger look for the money. If a piece is lightweight, pay special attention to the prongs holding the stone: are they sturdy? Do they grip the stone tightly? You won't be happy about the money you saved in gold cost if you lose your stone!

Diamond

This article is about the mineral. For the gemstone, see Diamond (gemstone). For other uses, including the shape ◊, see Diamond (disambiguation).

Diamond
A scattering of round-brilliant cut diamonds shows off the many reflecting facets.
General
Category	Native Minerals
Chemical formula	C
Identification
Molecular Weight	12.01 u
Color	Typically yellow, brown or gray to colorless. Less often in blue, green, black, translucent white, pink, violet, orange, purple and red.[1]
Crystal habit	Octahedral
Crystal system	Isometric-Hexoctahedral (Cubic)
Cleavage	111 (perfect in four directions)
Fracture	Conchoidal - step like
Mohs Scale hardness	10[1]
Luster	Adamantine[1]
Polish luster	Adamantine[1]
Refractive index	2.4175–2.4178
Optical Properties	Singly Refractive[1]
Birefringence	none[1]
Dispersion	.044[1]
Pleochroism	none[1]
Ultraviolet fluorescence	colorless to yellowish stones - inert to strong in long wave, and typically blue. Weaker in short wave.[1]
Absorption spectra	In pale yellow stones a 415.5 nm line is typical. Irradiated and annealed diamonds often show a line around 594 nm when cooled to low temperatures.[1]
Streak	White
Specific gravity	3.52 (+/- .01)[1]
Density	3.5-3.53 g/cm³
Diaphaneity	Transparent to subtransparent to translucent

In mineralogy, diamond is the allotrope of carbon where the carbon atoms are arranged in an isometric-hexoctahedral crystal lattice. Its hardness and high dispersion of light make it useful for industrial applications and jewelry. It is the hardest known naturally-occurring mineral. It is possible to treat regular diamonds under a combination of high pressure and high temperature to produce diamonds (known as Type-II diamonds) that are harder than the diamonds used in hardness gauges.^[2] Presently, only aggregated diamond nanorods, a material created using ultrahard fullerite (C₆₀) is confirmed to be harder, although other substances such as cubic boron nitride, rhenium diboride and ultrahard fullerite itself are comparable.

Diamonds are specifically renowned as a material with superlative physical qualities; they make excellent abrasives because they can be scratched only by other diamonds, borazon, ultrahard fullerite, rhenium diboride, or aggregated diamond nanorods, which also means they hold a polish extremely well and retain their lustre. Approximately 130 million carats (26,000 kg) are mined annually, with a total value of nearly USD $9 billion, and about 100,000 kg (220,000 lb) are synthesized annually.^[3]

The name diamond derives from the ancient Greek ἀδάμας (adamas) "invincible", "untamed", from ἀ- (a-), "un-" + δαμάω (damáō), "to overpower, to tame". They have been treasured as gemstones since their use as religious icons in ancient India and usage in engraving tools also dates to early human history.^[4][5] Popularity of diamonds has risen since the 19th century because of increased supply, improved cutting and polishing techniques, growth in the world economy, and innovative and successful advertising campaigns. They are commonly judged by the “four Cs”: carat, clarity, color, and cut.

Roughly 49% of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia. They are mined from kimberlite and lamproite volcanic pipes, which can bring diamond crystals, originating from deep within the Earth where high pressures and temperatures enable them to form, to the surface. The mining and distribution of natural diamonds are subjects of frequent controversy such as with concerns over the sale of conflict diamonds (aka blood diamonds) by African paramilitary groups.

$1.27 Million Diamond Jeans

Recession? What recession? Rumors abound that the economy is heading down, down, down and consumer confidence is danger of flat-lining. Obviously the analysts and the doomsday sayers have not been thorough in their research. I mean, if people are buying jeans for over $1.2 million, things can’t be that bad – can they?

During London Fashion Week, Secret Circus Clothing Company unveiled a $1.27 million pair of jeans and, by the close of the last show, announced the first pair of diamond-encrusted jeans had been sold.

The jeans are hand-made (obviously) and the back-pocket is embellished with 15 diamonds that include some rather large rocks: a 4.63 marquise diamond, 2 round brilliant six-carater diamonds, one 5.09 carat princess cut gem and a pear-cut diamond weighing in at 5.37 carats. Not forgetting of course 10 single carat diamonds.

Irma Matulionyte modeled them at the label’s launch at London Fashion Week in February, and since then, the brand has stirred up quite a buzz. The owner of the million-buck denims didn’t want to be named, but the company did state the jeans will fit a 27 inch waist. Practicality is, of course, another important consideration when buying jeans with diamonds. Before shoving them in the wash, let’s hope the laundry remembers to use the clasp that will remove the

JEWELRY NEWS

If you’re confused about what jewelry to wear on the golf course and what is considered ‘too much’ – we’ve got one golden rule – keep the jewels off the green – unless they’re on the putter. Confused – don’t be – if you’ve got around $4,000 to spare, your jewelry golfing woes are solved.

A German company, Barth & Sons, have developed a special ‘putter’ for lady golfers who place style and bling above practicality and budget. They’ve developed a custom-built putter with a 24kt gold-plated shaft and a head with crystal inlays (the basic version features pink but you can customize to almost color you want).

The packaging is done in a hand-crafted case of cherry wood and carries a personal engraving on the shaft or a gold plate on the Putter-Inlay if desired. The company also offers several possibilities to further personalize your GoldenPutter, for example, if crystals are a bit too plebian, you can opt for a more expensive model with gems and diamonds instead.

History's Most Famous Blue Gemstone

• The Star of India -- A 536-carat blue cabochon-cut star sapphire thought to be the largest cut sapphire -- is part of the Morgan-Tiffany Collection in the American Museum of Natural History in New York.
  
  
• The Blue Giant of the Orient -- A 446-carat sapphire from Sri Lanka.
  
  
• The Blue Belle of Asia -- This 400-carat stone from Sri Lanka is the largest sapphire in the British Crown.
  
  
• The Logan Sapphire -- A 423-carat cushion-cut blue from Sri Lanka. The piece was donated to the Smithsonian Institute in Washington, D.C., in 1960 by Mrs. John A. Logan.
  
  
• The Ruspoli -- A 135-carat rhomb-shaped (six facets) blue stone -- resides in France's National Museum of Natural History in Paris. During the 17th century, a Roman prince named Ruspoli sold the sapphire to a salesman, who in turn, sold it to King Louis XIV sometime before 1691. At the time it was the third most prominent gem in the French Crown Jewels.
  
  
• The Star of Asia -- A 330-carat blue cabochon-cut star sapphire -- also resides in the Smithsonian Institute.
• The Midnight Star -- A 116-carat, black cabochon-cut star sapphire -- is also in the American Museum of Natural History.
  
  
• The Star of Bombay -- A 182-carat, cabochon-cut, blue-violet star sapphire that was bequeathed to the Smithsonian by famous actress Mary Pickford.
  
  
• Catherine the Great's Sapphire -- A 337-carat, faceted oval blue owned by the Diamond Fund of Moscow.
  
  
• Kazanjian Sapphire Carvings -- Huge star sapphires from Australia have been carved into busts of U.S. presidents Lincoln (1,318 carats), Washington (1,056 carats), Eisenhower (1,444 carats), and Jefferson (1,381 carats). A fifth bust of Martin Luther King Jr., has also been carved from an Australian sapphire that originally weighed 4,180 carats and has a finished weight of 3,284 carats. And a sixth bust, Madonna of the Star, was carved from an Australian sapphire weighing 1,100 carats in the rough (525 carats cut). The Kazanjian Foundation of California owns the carvings.
  
  
• Lone Star Sapphire -- This 9,719-carat star sapphire of unknown origin was cut by Dallas cutter John Robinson in 1989.
  
  
• Unnamed Padparadscha (orange) Sapphire -- This 100-carat oval stone from Ceylon (Sri Lanka) resides in the American Museum of Natural History and is considered the world's largest fine Padparadscha.
  

Sapphire: History's Most Famous Blue Gemstone

Throughout history, sapphire, September's birthstone, has been considered the ultimate blue gemstone. This regal stone is so valued, it is actually the recommended gem for couples celebrating both their fifth and 45th anniversaries.

Although sapphire, a variety of corundum, is most valued in deep blue, the stone comes in a variety of hues, including pink, green, orange, yellow, purple, gray, black, brown, and colorless. Some sapphires even display a six-rayed star pattern when cut into cabochons (domed, unfaceted stones) and are appropriately called star sapphires. The only color you won't find a sapphire in is red -- the red variety of corundum is called ruby.

The word sapphire has roots in several languages: the Arabs called the stone "safir"; the Romans called it "sapphirus" (meaning blue); and the Greeks called it "sappheiros" after the island of sappherine in the Arabian Sea where sapphires were found at that time.

During the Middle Ages, sapphire was thought to represent purity of the soul. It was believed that the stone's color would darken if worn by an "impure" or wicked person. Sapphire was also considered the "Oracle's Stone" and was used to safeguard and foretell the future. The ancients believed the Ten Commandments were written on a sapphire tablet.

The world's finest sapphires used to come from Kashmir, India, but the mines there are now considered depleted. Stones from this region are characterized by their deep cornflower blue color and silky sheen. Incomparable sapphires were dug from one legendary ancient Kashmire mine, but its location is lost in the mists of time -- thus adding to the stones' mystique. Current important sapphire-producing locales include Australia, Myanmar (Burma), Sri Lanka and Thailand. Sapphires also can be found in Cambodia, China, Kenya, Nigeria, Tanzania and the United States (primarily in Montana). Large sapphires are quite rare, and are often given names such as with notable diamonds. Two of the most famous sapphires are part of the British Crown Jewels in the Tower of London. The St. Edwards Sapphire is a rose-cut gem of unknown size set in the finial cross of the Imperial Crown. It derives its name from Edward the Confessor, who wore the stone on a ring during his coronation in 1042. The Stuart Sapphire is a 104-carat oval mounted on the band at the rear of the Imperial Crown. Another famous sapphire associated with British royalty is the one that Prince Charles presented to Princess Diana to seal their engagement. The oval blue, 18-carat sapphire is surrounded by diamonds and set in sterling silver.

Here are a few of history's other notable sapphires. Many are on display in museums and private collections around the world:

Tips for Selecting the Right Bench Stone for Sharpening

With so many types of stones for sharpening, it can be difficult to determine what the best stone is for your woodworking needs. Fortunately, the variety of stone materials will allow you to select a material that will meet your needs and stay within your budget.

The three main types of bench stones are oilstones, waterstones and diamond stones. Since every woodworker’s needs and preferences are different, understanding the advantages of each stone will allow you to be a more informed purchaser of sharpening stones.

Oilstones
Oilstones are the traditional stones that have been popular for years. Today they are available in man-made and natural stones. The man-made stones are made of either silicon carbide or aluminum oxide abrasives. These are generally available in coarse, medium and fine grades. The natural stones are made of novaculite and are available in grades such as Soft Arkansas, Hard Arkansas, and Hard Translucent Arkansas; the harder the grade, the finer the grit of the stone. The natural stones are generally finer grits than the man-made stones so it is common to have both man-made and natural oilstones in your sharpening kit.

As the name suggests, oilstones use oil as a lubricant and to remove the swarf to keep the stone from getting glazed. The oil used is generally a light mineral oil.

Advantages	Disadvantages
Lower cost Stay flat longer than waterstones	Slower Cutting Use oil as lubrication

Waterstones
Waterstones have become very popular among woodworkers because they cut faster than oilstones. Like the oilstones, waterstones are available in both a man-made and a natural variety. However, in the western world, the man-made stones are significantly more popular.

Most waterstones are made of aluminum oxide abrasive. While this is the same type of abrasive material as used in some oilstones, the stones are quite different. First, unlike oilstones, waterstones use water to remove the swarf. Using water makes it easier to clean up and more convenient to use. Secondly, waterstones cut faster than comparable oil stones because the binding material that holds the stone together is softer. The softness of the stone allows the stone to cut faster because sharp new material is constantly being uncovered. However, the softness is also the biggest disadvantage of the waterstone because it must be flattened regularly.

Advantages	Disadvantages
Fast Cutting Uses water as lubrication	Must be flattened regularly

Diamond Stones
Diamond stones may not be as popular now but woodworkers seem to be catching on to the advantages. Unlike oil and water stones, diamond stones are all man-made. These industrial diamonds are applied to a metal backing to create an abrasive surface.

The diamond stone can be extremely versatile. It can be used to sharpen any woodworking tool. It can even sharpen carbide tipped router bits that both oil and water stones can’t touch.

Diamond stones do not wear unevenly because the diamond surface is so hard. Because of this diamond stones can be used to flatten oil and water stones.

Like the water stone, diamond stones use water to remove the swarf.

Advantages	Disadvantages
Fast Cutting Stay flat Use water as lubrication Can flatten other stones	Initial cost

Choosing a Hybrid Option
There is no reason to stick with only one type of stone. Another option is to choose the best qualities of each stone and use them to your advantage. The diamond stone works so well on coarse work because it cuts aggressively and stays flat. The waterstone is great for putting on the final edge. We've selected the best hybrid combination and included a coarse/fine diamond stone with an very fine 4000/8000 waterstone. Because both stones use water, they are very compatible. View the money saving woodworking stone kit.

The New Diamond Age

Armed with inexpensive, mass-produced gems, two startups are launching an assault on the De Beers cartel.
Next up: the computing industry.

By Joshua Davis

Aron Weingarten brings the yellow diamond up to the stainless steel jeweler's loupe he holds against his eye. We are in Antwerp, Belgium, in Weingarten's marbled and gilded living room on the edge of the city's gem district, the center of the diamond universe. Nearly 80 percent of the world's rough and polished diamonds move through the hands of Belgian gem traders like Weingarten, a dealer who wears the thick beard and black suit of the Hasidim.

David Clugston Yellow diamonds manufactured by Gemesis, the first company to market gem-quality synthetic stones. The largest grow to 3 carats.

"This is very rare stone," he says, almost to himself, in thickly accented English. "Yellow diamonds of this color are very hard to find. It is probably worth 10, maybe 15 thousand dollars."

"I have two more exactly like it in my pocket," I tell him.

He puts the diamond down and looks at me seriously for the first time. I place the other two stones on the table. They are all the same color and size. To find three nearly identical yellow diamonds is like flipping a coin 10,000 times and never seeing tails.

"These are cubic zirconium?" Weingarten says without much hope.

"No, they're real," I tell him. "But they were made by a machine in Florida for less than a hundred dollars."

Ian White A microwave plasma tool at the Naval Research Lab, used to create diamonds for high-temperature semiconductor experiments.

Weingarten shifts uncomfortably in his chair and stares at the glittering gems on his dining room table. "Unless they can be detected," he says, "these stones will bankrupt the industry."

Put pure carbon under enough heat and pressure - say, 2,200 degrees Fahrenheit and 50,000 atmospheres - and it will crystallize into the hardest material known. Those were the conditions that first forged diamonds deep in Earth's mantle 3.3 billion years ago. Replicating that environment in a lab isn't easy, but that hasn't kept dreamers from trying. Since the mid-19th century, dozens of these modern alchemists have been injured in accidents and explosions while attempting to manufacture diamonds.

Recent decades have seen some modest successes. Starting in the 1950s, engineers managed to produce tiny crystals for industrial purposes - to coat saws, drill bits, and grinding wheels. But this summer, the first wave of gem-quality manufactured diamonds began to hit the market. They are grown in a warehouse in Florida by a roomful of Russian-designed machines spitting out 3-carat roughs 24 hours a day, seven days a week. A second company, in Boston, has perfected a completely different process for making near-flawless diamonds and plans to begin marketing them by year's end. This sudden arrival of mass-produced gems threatens to alter the public's perception of diamonds - and to transform the $7 billion industry. More intriguing, it opens the door to the development of diamond-based semiconductors.

Diamond, it turns out, is a geek's best friend. Not only is it the hardest substance known, it also has the highest thermal conductivity - tremendous heat can pass through it without causing damage. Today's speedy microprocessors run hot - at upwards of 200 degrees Fahrenheit. In fact, they can't go much faster without failing. Diamond microchips, on the other hand, could handle much higher temperatures, allowing them to run at speeds that would liquefy ordinary silicon. But manufacturers have been loath even to consider using the precious material, because it has never been possible to produce large diamond wafers affordably. With the arrival of Gemesis, the Florida-based company, and Apollo Diamond, in Boston, that is changing. Both startups plan to use the diamond jewelry business to finance their attempt to reshape the semiconducting world.

But first things first. Before anyone reinvents the chip industry, they'll have to prove they can produce large volumes of cheap diamonds. Beyond Gemesis and Apollo, one company is convinced there's something real here: De Beers Diamond Trading Company. The London-based cartel has monopolized the diamond business for 115 years, forcing out rivals by ruthlessly controlling supply. But the sudden appearance of multicarat, gem-quality synthetics has sent De Beers scrambling. Several years ago, it set up what it calls the Gem Defensive Programme - a none too subtle campaign to warn jewelers and the public about the arrival of manufactured diamonds. At no charge, the company is supplying gem labs with sophisticated machines designed to help distinguish man-made from mined stones.

Ian White "I was in combat in Korea and 'Nam. You better believe that I can handle the diamond business," says Gemesis founder Carter Clarke, center. His lieutenants have 27 diamond-making machines up and running -- with 250 planned -- at this factory outside Sarasota, Florida

In its long history, De Beers has survived African insurrection, shrugged off American antitrust litigation, sidestepped criticism that it exploits third world workers, and contended with Australian, Siberian, and Canadian diamond discoveries. The firm has a huge advertising budget and a stranglehold on diamond distribution channels. But there's one thing De Beers doesn't have: retired brigadier general Carter Clarke.

Carter Clarke, 75, has been retired from the Army for nearly 30 years, but he never lost the air of command. When he walks into Gemesis - the company he founded in 1996 to make diamonds - the staff stands at attention to greet him. It just feels like the right thing to do. Particularly since "the General," as he's known, continually salutes them as if they were troops heading into battle. "I was in combat in Korea and 'Nam," he says after greeting me with a salute in the office lobby. "You better believe I can handle the diamond business."

Clarke slaps me hard on the back, and we set off on a tour of his new 30,000-square-foot factory, located in an industrial park outside Sarasota, Florida. The building is slated to house diamond-growing machines, which look like metallic medicine balls on life support. Twenty-seven machines are now up and running. Gemesis expects to add eight more every month, eventually installing 250 in this warehouse.

In other words, the General is preparing a first strike on the diamond business. "Right now, we only threaten the way De Beers wants the consumer to think of a diamond," he says, noting that his current monthly output doesn't even equal that of a small mine. "But imagine what happens when we fill this warehouse and then the one next door," he says with a grin. "Then I'll have myself a proper diamond mine."

Clarke didn't set out to become a gem baron. He stumbled into this during a 1995 trip to Moscow. His company at the time - Security Tag Systems - had pioneered those clunky antitheft devices attached to clothes at retail stores. Following up on a report about a Russian antitheft technology, Clarke came across Yuriy Semenov, who was in charge of the High Tech Bureau, a government initiative to sell Soviet-era military research to Western investors. Semenov had a better idea for the General: "How would you like to grow diamonds?"

---

Contributing editor Joshua Davis (jd@joshuadavis.net) wrote about the Army's tactical Internet brigade in Iraq in Wired 11.06.

PRIVACY POLICE

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Stamp collecting

Let's change the subject. To stamps. Yes indeed, the little sticky things one affixes to envelopes. Daydream for just a moment…
…Here's your nightmare. A postage stamp was produced in Burundi in 1945 and is considered the world's most valuable collectors' stamp, primarily because of a printing error. It seems that the dot on the "i" in Burundi was forgotten in one batch. And before the error was caught, a few went out. So this is the world's rarest postage stamp. Now you, being the clever type that you are, get hold of some of the regular stamps and carefully erase the dot on the i. Then you sell them as the very rare type. But horror of horrors, your customers call in the police. As the police take you away shrieking and babbling you protest: "Why me? I didn't add anything. Furs are treated, fruit is treated, everything is treated nowadays." But the cops do not listen. Instead you are thrown in some hell hole of a jail with inmates whose only retort is "Why you? Why you ? Ha ha ha ha hee hee ha ha ha……… bend over."

Deep diffusion– total oneness (or just TV evangelism)?

Do deep surface-diffusion treated sapphires (DSDTCs) represent gem treatment nirvana? Or are they just the Disneyland representation of the place? The original Linde patents claimed a maximum penetration of 0.50 mm, while the deepest penetration measured on the D-SDTCs is 0.40 mm. In all other respects they resemble the Linde material. So, gentle readers, this is what I say: "No way, Ray!"
But this does beg the question of why deep diffusion has created such a furor in Bangkok when the earlier activities by Thai burners raised not even a ripple. Good question. Mighty good question. It just may have something to do with the fact that the profit from the earlier doings went to local traders, while those of today go to heathens from out of town. Or maybe (and hopefully) people have finally realized that the gem-treatment genie, once out of the bottle, is a bit difficult to contain.

The deep diffusion mutant– Kill it before it mates

Beginning in mid-1989, I heard about deep surface diffusion treated corundums, or D-SDTCs. Yes, that's right – deeeeep surface diffusion-treated blues. In April, 1990, after learning who was involved, I approached the principals (Las Vegas-based Gem Source) for more info. They were generous in offering both samples for study and information about their marketing plans. They planned, and have, sold the material for what it is – surface-diffusion treated corundum.
But all was not well in the Land of Blue. Jeffery Bergman of Gem Source told me in June 1991 that he had received more than ten death threats, presumably coming from paranoid Bangkok dealers who feared that the D-SDTCs would wreak havoc on the natural sapphire market. Bad craziness indeed, but it couldn't help but bring a smile to my face – the very idea that something might destroy the natural blue sapphire market. "What market?" thought I, "there are practically no natural blue sapphires being traded in 1991."

Return of the diffusion zombie

In mid-1988, I again began to see surface-diffusion treated corundums, or SDTCs, in Bangkok, but this time with a more sinister glint. It had always been in the back of my mind that, rather than taking near-colorless sapphires and treating them to a deep blue, some day treaters were going to take a stone which already had a lot of color of its own and just give it, via surface diffusion, a bit more. This is what happened in mid-1988 – to such an extent that I reported the matter to the International Colored Stone Association.
Treaters were taking medium-quality Kanchanaburi sapphires that had a lot of color of their own, but were heavily zoned, and diffusing their problems away.
Because certain burners were disappointed that their best efforts could still be identified, they embarked upon a campaign of threat and innuendo against Bangkok gemologists. But this had little effect, eventually giving way to…

Surface diffusion 101

The surface diffusion treatment was first developed at Union Carbide's Linde division in the US. Linde, the first company to synthesize star corundum, had problems obtaining both uniform color and uniform silk in the same stone. Here's the recipe for cooking sapphires the Linde way:
Pack stones in a crucible filled with the kind of chemicals which produce both rutile silk (Ti) and color (Ti, Fe, Cr, etc.).
Heat to near the melting point (1800–1900° C) for several days or even weeks. Periodically recharge the crucible with chemicals.
After cooling, lightly repolish, and voila – the gems now have color and/or stars.

How does it work? Like this: when a stone is heated to near the melting point, the crystal lattice is expanded to the maximum. Heat it too much and the bonds break completely. That's melting (and that's tough titty if it's your stone). But if you heat it to just below the melting point, where the bonds stretch but do not break, the gem will absorb the chemicals, creating color, asterism or both. However, atoms of Fe, Ti and Cr are fairly large and so cannot move easily into the stone. Thus the color and asterism are confined to a thin layer (0.10 to 0.50 mm) near the surface. This process was patented by Union Carbide in 1975–1977 and is termed surface diffusion.
Surface diffusion works best on stones which have little or no color of their own, as it makes little sense to add color to something that already has plenty. The starting material is generally near-colorless sapphire from Sri Lanka. Due to the shallow penetration of surface-diffused color, stones must be cut (but facets left unpolished). After treatment the surfaces will be pockmarked from the high temperatures. And so the stones are lightly repolished (with the emphasis on lightly), to leave intact as much of the color layer as possible. Too heavy a hand on the polishing wheel results in both loss of color and $$$$.
Both faceted and star sapphires of blue and orange colors treated in this way first appeared in the gem trade in the late 1970s and early 1980s. Initially the stones were produced by the Swiss company Golay Buchel, which bought the process from Union Carbide. Later, stones treated in Thailand and elsewhere appeared. But they soon disappeared when gemologists became familiar with their characteristics. And by the mid 1980s they were rare indeed.

Sapphire stone-Wise

Hard to imagine this amazing blue sapphires net late autumn or winter, when the sky is gray clouds delayed. But so easily recall the May clean clear skies, beautiful waves sapphires. Since ancient times, philosophers and poets called a sky high ion. This stone can have all the blue-sky shades of bright blue and deep blue morning until evening. But, in addition, can be deposited, and most others are playing sunset colors-yellow, pink, orange and mauve. waves beauty sapphires. Sapphire can be colorless white, green, brown and purple, magenta, golden yellow, pink persikovo-. But the color sapphires is certainly blue. Blue Ion usually associated consistency and reliability. That is why in the world have a tradition of donating to the betrothal future wife is deposited, as a symbol of loyalty. Stone Wise In ancient stone church was deposited servants and teachers and elders. Priest temple of Jupiter has always been deposited in the ring with the index finger. Lie decorated clothing clergy Judea and India, they have been decorated crown Cleopatra. Color sapphires expensive always valued and always considered prestigious. First described in the literature colored sapphires Pliny in "Natural History". In his writings he made a number of scientific evidence on the properties of this mineral: the colour, glamour, change hues with rotating stone. In Renaissance jewelry display sapphires have been particularly fashionable in the courtyard of the King of France, as well as in Italy and Spain. Always thought that ion cools passion, grace calm, calm, modesty and unselfishness. Not to be confused with rubies Sapphire belongs to a group of corundum, which was characterized its hardness. On a scale of the mineral Moosa second in hardness only diamond. This firmness is deposited, even for daily socks in the jewellery decorations. His edge over the years, virtually erased. It is difficult to keep on rock scratches.

The group also has corundum ruby. And, in fact, this was the same stone, but with a different colour. For ease of classification profession precious stones, it was decided to call all the red corundum rubies. The remaining colors, including green, orange, pink, white and the other is related to logistics, although they put in a separate subgroup. Lie not blue or fantasy called "fensi." Most rare orange-ion with light pink shade that came to be known - padparadzha or lotus flower. Another rarity is deposited fashion. Its surface can be seen rolling shestiluchevuyu stars reflected light. Such sapphires are often proud to collectors or fans proud individual jewellery. Two identical sapphires "fensi" virtually impossible to find. Our minds can hardly be accomplished by explaining that sapphires amazing colors and celestial hues are deep in the bowels of the Earth. The most beautiful sapphires are in Kashmir (India), they also the most expensive. Surprising beauty coloured sapphires from Burma (Kanchanaburi area), many beautiful sapphires are in Sri Lanka (Ratnapura district). There are deposits of sapphires in Madagascar. A collection Leopard Jewelry collected the best sapphires from the known world.