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lady luckA fancy vivid yellow diamond weighing a whopping 77.77 carats is expected to be the top lot at Sotheby’s Hong Kong, with a pre-sale estimate up to $7.7 million.

Clearly the top lot has auspicious ties to the number seven. In the Western world, seven is considered the luckiest of all numbers; many a gambler has dreamed of hitting the 7-7-7 slot machine jackpot. For potential Asian buyers, seven is a lucky number that signifies togetherness, and the yellow hue is also symbolic of royalty and power.

The “Lady Luck Diamond” boasts a VS2 clarity and a pure fancy vivid yellow, the most desirable saturation for colored diamonds. Pure yellow diamonds owe their coloration to nitrogen atoms dispersed throughout the crystal matrix, which is extremely hard to penetrate. The amount of nitrogen present determines a yellow diamond’s saturation level, which is why the more intensely saturated gems are extremely rare and valuable.

Flanked by five-carat heart-shaped diamonds on either side, the “Lady Luck” is presented as the lady luck 2centerpiece of a three-stone ring in rich 18 karat yellow gold. It can also be detached and worn as a pendant on its own.

The “Lady Luck” is sure to appeal to a wide audience of bidders later this month at Sotheby’s “Magnificent Jewels and Jadeite Sale” at the Hong Kong Convention and Exhibition Center. The auction comprises 320 lots in total, including rare colorless and colored diamonds, gemstones, and signed pieces from the Art Deco period. Total sales expected to be generated are over $100 million.

 

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dom pedroThe Dom Pedro is a stunning example of March’s official birthstone, and is also the largest faceted aquamarine specimen in the world.

At 1,363 carats and nearly 36cm tall, the fantasy-cut Dom Pedro aquamarine can certainly hold its own – even when on display at the Smithsonian’s Janet Annenberg Hooker Hall of Geology, which houses other highly valuable gems like the Hope Diamond and the De Young Red Diamond.

The Dom Pedro was cut from part of a meter-long, 45kg aquamarine crystal that was discovered in the 1980’s in the Brazilian state of Minas Gerais. While in transportation, the crystal actually fractured into three separate pieces. The two smaller pieces were eventually cut into many smaller gemstones, but the largest was kept intact as it embodied an exquisite greenish-blue hue and amazing clarity. This largest piece was sold to none other than legendary gem-cutter Bernd Munsteiner, known as the “Father of the Fantasy Cut” and “the Picasso of Gems”.

According to the Smithsonian, the first time that he laid eyes on the gem he proclaimed that it was love at first sight!

Munsteiner spent over four months studying the rough and making hundreds of sketches before he settled on the aquamarine’s dom pedro munsteinerfinal pattern. It was to be his most famous “fantasy cut” gem, a cutting technique where negative cuts are faceted into the back of a gemstone to reflect the light within.

During the six months it took to hand cut the gem, he was never concerned about the final carat weight; he opted instead to cut for beauty and brilliance, rather than price. “When you focus on the carat weight, it’s only about the money,” said Munsteiner. “I cannot create when I’m worried about the money.”

The finished masterpiece was unveiled at the 1993 Baselworld Gem Fair, and later bought by private collector Jane Mitchell and her husband Jeffrey Bland. They gifted the stone to the Smithsonian’s National Gem and Mineral Collection in 2011, and by the end of 2012 Dom Pedro was added to the permanent exhibition and continues to be a top attraction.

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CitrineWith its range in color from sunny yellow to bronze deep orange hues, what better stone to represent the falling leaves of autumn than citrine? One of the official birthstones of November, citrine is a member of the mineral family quartz.

Currently the world’s largest faceted citrine resides in the “Special Exhibit Gems” of the Art Natura museum in Spain, a natural science museum that is home to an extensive collection of colored gemstones. Known as “The Malaga” in tribute of its host city, this oval shaped gem is an enormous 20,200 carats – equivalent to 4 kilos! It neighbors another gemstone of gigantic proportions: the “Eldorado”, a 31,000 carat imperial topaz which also happens to be the other birthstone of November.

Despite its size, “Malaga” has very minor imperfections and is considered nearly flawless. Along with its exceptional color, even distribution, transparency and purity, “Malaga” is truly a world-class gem. Citrine crystals that are found usually measure only a few cm across, and the ones that are larger in size generally lack in quality and are used for decorative purposes rather than jewelry.

The rough that formed “Malaga” was originally discovered in 1990 in Brazil. Due to the complications of the process of cutting and polishing a stone this large, the rough was left untouched for nearly two decades until 2009 when a team of gem cutters took on the challenge. With all of the special considerations needed for a stone of this size, it took over a year to bring to its polished form.

Brazil is the largest producer of the world’s supply of citrines; other important sources include Bolivia, United States, and Madagascar.

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Faces“Faces of Eternity” is the new exhibition being displayed at the Gemological Institute of America’s headquarters in Carlsbad, California. The exhibition features a collection of 15 carved skulls by a Peruvian artist Luis Alberto Quispe Aparicio. The skulls are made from various large gemstone crystals, ornamental rocks and silver and gold vermeil. It’s inspired by the contrast of human mortality and the timelessness of gemstones.

“From fossilized whale bone to rainforest jasper, and from pink opal to peanut wood agate, Aparicio chose materials from a gem lover’s dream. Each skull has a distinctive look and feel to it, making this collection fascinating on both a gemological and artistic level,” said Terri Ottaway, GIA museum curator.

One of the skulls called “Everlasting Youth” was carved from Mozambican aquamarine with rock crystal quartz and gold vermeil.  “Top Hat Gentle-skull” is made in rock crystal quartz from Madagascar with snowflake obsidian and gold vermeil. Another called “Chocolate with Peanut Butter” skull is made with petrified palm  wood agate from Australia with obsidian and gold vermeil.

“The skulls collection was one of my favorite to create. By carving natural gemstones with a combination of lapidary art and metal smith techniques, you can really see how the colors and textures in each stone brings each piece to life,” Aparicio said.Faces

His whole collection is comprised of 26 pieces all made within one year. The other 11 pieces not found in the exhibition are in private collections in the USA, the U.K, France and Russia. He works with his sister Sylvia at their family owned company called Neoart Peru established in 1975. The company specializes in ruby carvings with a focus on wildlife inspired themes using very rare and unusual gemstones.

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Lead-glass filled rubies have been creeping slowly into the jewelry market, and are now the most abundant ruby material used.  Even from the wholesale level they are sometimes undisclosed, making their way to retailers as loose stones or finished jewelry; which should be a widespread concern for jewelers and buyers alike.

What exactly are lead-glass filled rubies and why is this a big deal?

Lead-glass filled rubies, also known as composite rubies, typically start out as very included, dark ruby rough that would otherwise be unworkable. The rough or polished stone is then treated multiple times by being exposed to high heat while submerged in a lead-glass solution, which is a permanent fusion process of the ruby material with the lead-glass filler. The result is a gemstone far better in appearance of the rough it came from, but at a cost of the stability and durability of the stone. Due to a significant portion of the gem being composed of glass, these stones are sensitive to high temperatures, many cleaning solutions, and exposure to direct sunlight. A simple jewelry repair or maintenance process such as resizing or polishing can be detrimental to a lead-glass filled ruby.

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If the end result from this enhancement has a completely different chemical makeup, is considerably more vulnerable to damage, and contains more filler than corundum – how can you still call it a natural ruby? It is more accurate to describe these gems as composite, reconstituted, or even man-made rubies. The lead-glass serves as the “glue” that holds together the skeleton of the actual ruby.

Lead-glass rubies should not be confused with “treated” rubies.

As this type of treatment is relatively new to the industry, many market these rubies as being “treated” when it should be directly listed as lead-glass filled. Other traditional and widely accepted enhancement procedures (mainly heat-treatment and fillers) do not affect day-to-day handling of the stone.

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Why use lead-glass?

The reason lead-glass is used is because it can be formulated so that its refractive index (R.I.) is the same as ruby’s. The refractive index of a stone relates to the way light moves through it. The greater the difference between the R.I. of each substance, the more easily you can see the different components; the closer the R.I., the more difficult it is to see them. If the R.I. is the same for both substances, you cannot distinguish where one ends and the other begins.

What is the difference between lead-glass in composite rubies and the silica glass fillers in “treated” rubies?

  1. Silica glass is more durable than lead-glass
  2. Rubies that are treated with silica glass use much less of it than composite rubies use lead-glass
  3. The lead-glass cannot be separated from a composite ruby without causing irreparable damage; silica glass filler can be safely removed from a treated ruby to return to its original state, and after it can be refilled
  4. Because lead-glass cannot be safely removed, composite rubies cannot be accurately graded for clarity or color. It is possible to grade for color and clarity with silica glass rubies (after removal of the filler)
  5. Carat weight – the representative carat weight of composite rubies is misleading because it accounts for the combined weight of the lead-glass and ruby material. What makes it even worse is that lead-glass is 50% heavier! Since traditionally glass-treated rubies use very little silica glass, it has very little, if any, impact on the carat weight.
  6. Value – all composite rubies are very inexpensive, at the wholesale level they only go for a few dollars per carat; treated/natural rubies start at 20 times the value and up, depending on quality
  7. Detectability – silica glass filled rubies is easier to spot with the naked eye, as there is an R.I. difference between materials. Most lead-glass filled rubies are difficult to identify by the naked eye because the R.I. of lead-glass and ruby is the same, but close up under a jeweler’s microscope the tell-tale air bubbles and flashes of blue are a dead giveaway.

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The bottom line for a buyer would be to find a retailer who has someone who can identify any treatments made to a stone, a Graduate Gemologist or similar who has undergone formal gemological training. At the very least, do not buy any rubies without an official gemological certification stating its treatments (if any). You pay for what you get. There are no discounts for quality rubies, they are very rare and in high demand. Use common sense, get a stone with a lab certificate or have it certified, and buy from a knowledgeable jeweler.

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Read Part 1: Can Diamonds be Chipped?  and Part 2: Tips to Prevent Damaging Diamonds

Accidents happen. It’s hard not to get upset when your diamond gets chipped, but understand that it’s not uncommon. It is part of the risk you take when wearing jewelry; although diamonds sustain less damage in everyday wear and tear than other gemstones, they are not indestructible.

First of all, you need to evaluate the chip(s) in your diamond. How big is it relative to your diamond? Is it instantly noticeable? Is it something you can live with? Keep these questions in mind when you bring your diamond ring to a specialist for an in-depth appraisal. A Graduate Gemologist and/or certified Appraiser will be able to assess the chip(s) effect on the diamond’s structural integrity, value, and can suggest viable options based on their evaluation.

If the chip is small and lies on the girdle edge, you may be able to reset the diamond with metal covering the area of the chip. The purpose of this is two –fold: the metal will act as a barrier to protect the chip from further stress which can lead to more extensive damage, and it will also hide the chip from view. Styles such as Bezel, Half-Bezel, Bypass, or even the addition of new prongs can achieve this effect.

Another option may be to recut the diamond. This option should be considered if your stone is of high monetary or sentimental value, as the process is quite costly. Not all diamonds are good candidates for a recut however. If the stone has chips in multiple places and/or the chip is large, it may not even be considered for a recut. Similarly, a stone would not be recut if its internal inclusions pose a significant damage risk during the process. This is a very specialized area of jewelry repair that needs to be done by a diamond cutter with great care. Talk with your jeweler to see if this would be possible for your stone.

If all else fails, you may consider replacing the diamond. Depending on your insurance policy or jeweler trade-up policy, this can also be a cost-effective option.

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Diamond BoxWe finished off with Part 1: Can Diamonds be Chipped?

They say an ounce of prevention is worth a pound of cure. In taking care of your diamond jewelry, this is especially important. For something that can last you forever, it does require some amount of maintenance to keep it in its best shape.

Routine checkups at your jeweler (recommended is about every 6 months) is key. They have the tools and expertise to evaluate your jewelry for any compromise in the structure or integrity. Checking settings for loose stones, worn prongs or metal can prevent diamonds being exposed or even falling out.

After that, it’s all up to you. Be slightly more cautious when wearing rings, diamonds can chip when coming in contact with any hard surface such as doorknobs, kitchen countertops, or car windows. Ideally you would want to take your rings off when doing any manual work with your hands: lifting heavy objects, doing chores, cooking, gardening, and more. The more your diamond jewelry comes into contact with other objects, the more likely it is to damage. That’s why rings are the most susceptible and show signs of wear more easily; bracelets are a close second followed by necklaces and earrings, which are relatively safe.

As diamonds are most easily damaged by other diamonds, take care in storing your diamond jewelry separately when not wearing them. Every piece should have its own compartment and not be touching another diamond piece. For necklaces, lay them out carefully and store them in a spacious box, not a pouch where it can move against itself.

Another factor that contributes to the risk of damaging diamonds is present in the diamond’s structure: inclusions. Inclusions are the naturally occurring “imperfections” in the molecular crystal of the diamond, and come in many forms. Not all inclusions increase the risk of damage; it all depends on the size, location, and type of inclusion present. Inclusions to pay particular attention to are feathers, twinning wisps, or cavities that reach the surface close to the girdle, where impact is the likeliest to happen. It’s best to consult with your jeweler or someone with formal diamond training such as a GIA Gemologist to discuss the role inclusions play in your diamond’s integrity.

Read on to Part 3: What to Do With a Chipped Diamond

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footballsizegem2This football sized gem has come out of hiding and is looking for a new home but one that will make sure the unique marvel can get viewed on a regular basis. The giant sapphire gem was carved and designed by an Italian artist Alessio Boschi. It took two years to complete and was finished by the year 2000. The 28cm Millennium Sapphire was found in Madagascar in 1995. It weighed 90,000 carats while in its rough state but lost about a third of its mass because of the carving process. The carvers practiced each 134 design on pieces of lapis lazuli.

The sapphire is a tribute of human genius and each 134 design is a different subject including faces. Some of the human genius that is carved onto this stone are faces of Michelangelo, Shakespeare, Martin Luther King, Beethoven, and Albert Einstein. It also has representations of the Great Wall of China, the Pyramids of Giza, and Gutenberg’s printing press.

Currently a union of investors with Daniel McKinney as the leader owns the Millennium Sapphire. In the past 15 years the magnificent carving has only been on public display twice. In the times its not on display it is tucked away in a safe of an undisclosed U.S location. The union agreed that this amazing work needs to be enjoyed by the public. The owners didn’t want to put it up for auction because they wouldn’t be able to control the buyer and someone might have it just for their private display.

“We’ve got offers in the past from various millionaires and billionaires from China and other places to buy it for themselves,” McKinney told The National, “but they would probably put it in their mausoleum and it would be lost to the world.”

“It would be great if it could be displayed in a museum as that’s why it was created,” said Scott Chapman, an associate of McKinney. “The consortium wants to be able to display it and show it.”

For now it is on sale if the right buyer can come up with $180 million and promise to have the 61,500 carat gem to be housed where the public can view it regularly.

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Sapphire HeatSapphires come in every colour except a certain shade of red called a ruby. There are several different methods to enhance and improve the colour and clarity of a sapphire. Commonly practiced treatments are heating a natural sapphire to heighten the look of the stone. Heating a sapphire is done by placing it in a furnace at temperatures between 500 and 1800°C for several hours.  Another way is by heating it in a nitrogen-deficient atmosphere oven for seven days or more. With this process the stones become bluer and lose some of their inclusions like the silk kind. When higher temperatures are used the stone loses all silk inclusions and under magnification the stone is clear. Sapphire and other gemstones being heat treated goes back to Roman times. An untreated natural stone is somewhat rare and will be sold with a certificate from a gemology lab.

Another treatment is diffusion to add impurities to the sapphire and enhance the colour. A type of chemical element called beryllium is diffused into the sapphire with very high heat. Many colours of sapphires are being treated with beryllium. At first orange sapphires were created with this process but now the process has been advanced and many different colours can be produced.

Sapphire Heat

On the other hand a type of sapphire called “Yogo” sometimes does not need to be heat treated because of their natural cornflower blue colour. These sapphires have a deep blue uniform clarity and are generally free of any characteristics or inclusions. Intergem Limited started marketing the Yogos in the 1980’s as the world’s only untreated sapphire guaranteed. By 1982 heat treatment became a major issue at that time 95% of all the worlds sapphires were being heated to bring out their natural colour. The guarantee of Intergems marketing of Yogos set them apart of many in the gem industry. The issue ended up on front page of the Wall Street Journal in 1984 with the headline “Sapphire Marketer Upsets the Gem Industry.”

How to tell if your sapphire has been heat treated? Usually a small UV lamp can help check the gem quickly for any potential alterations. Any stones that have a chalky florescence are most likely heat treated. Taking it to a certified gem dealer with GIA industry standards is a good way to have them test it.

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DiamondThe most flawless, biggest briolette ever to surface at auction weighing at a stunning 75.36ct broke records! This diamond was sold for a world record at $11,145,734 from an anonymous buyer at Christie’s Hong Kong’s Magnificent Jewels sale. This pendant necklace was originally valued at a pre-sale low estimate of $8.5 million, which it easily surpassed.  It did fall short of its high pre-sale estimate of $12.5 million.

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The briolette is a traditional cut popular in the Victorian times but has recently become more popular in precious and semi-precious stones. It is a stone cut into a three-dimensional waterdrop shape.  Its elegant pear shape with cut facets dangles below a marquise-cut purplish-pink diamond. Adorned with stations of smaller briolettes with 18 karat white and rose gold adjustable neck chain, this piece is a classy stunner!

An auction spokesperson said the diamond was “perfect,” and had the proof of an assessment with the Gemological Institute of America. The GIA rated the stone Type IIa, which is the top quality grade.  The diamond is similar to the British Queen Elizabeth’s one she has set in her crown. Christie’s jewellery specialist, Chiang Shui-Fung, says the diamond is extremely rare.

The briolette is special because they have to find a piece rough and big enough to cut into that style. The diamond came to an American dealership named William Goldberg, as a 160.5- carat rough weight and had to be shaped into the now 75.51 carat diamond. To achieve this brilliant rare cut William Goldberg had to sacrifice more than half the stone’s weight in the meticulous cutting process. The diamond is now a stunning piece and will be remembered as a historical record breaking event.

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