Bad Diamond Certification alert!!!!!

NATIONAL JEWELER MAGAZINE in their online publication just provided the following information (03/26/12).  This sort of information is highly important to remember if you find yourself wanting to only evaluate a diamond certification instead of inspecting the gem itself. 

Antwerp--HRD Antwerp announced Friday that it has fired four diamond graders for what the laboratory is calling “an unprofessional act” and is conducting an internal investigation into the matter.

Lab General Manager Georges Brys said on Friday that three of the graders were let go last Thursday and the fourth on Friday. He would neither confirm nor deny reports that the firings were related to bribery.

“We have not made any statements in that direction,” he said.

Brys also denied reports that the police were involved at this point, noting that the internal investigation will indicate whether it’s a criminal matter that will require police intervention.

“They were fired based on the fact that they have made a professional mistake,” he said. “We have not yet any evidence pointing in that direction.”

He said the graders involved had been employees of the lab between eight and 11 years. It’s unclear for how long these “professional mistakes” have been occurring, and it is also unknown how long the internal investigation will take, Brys said.
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Rapaport Market Comment for January 13, 2012

International diamond markets show stable pricing, but trading remains cautious. Uncut diamond rough selling at slightly lower prices to dealers as cutters expect miners and distributors to reduce high asking prices from those of late last year. Solid Far East diamond demand ahead of Chinese New Year. Global jewelry retailers report steady Christmas sales, however with tight profits due to higher gold and gem costs.  Expect to see stable jewelry and gem  prices in the U.S. retail market due to strong foreign demand using a larger portion of the available goods.

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A diamond's lab certificate is just an opinion

The basic thoughts and original draft of this article belong to Aleah Siegle of Olympian Diamond.  I have changed her text a little, but the driver was her original work.  Her article appeared in In Store Magazine.........

As you to look for a diamond to purchase you should realize that the primary reason a diamond is lab certified is to identify the gem and describe its features in detail. Many jewelers and customers wrongly assume that a lab certification, be it GIA, EGL, IGL or any other lab, is a guarantee of high quality -  it's not.

If you read the small print disclosure on diamond grading certificates it typically states that the certificate is NOT an appraisal, guarantee, or warranty.  The color and clarity are the OPINION of the lab grader at that time the stone was being observed and assessed.

 The grading results may differ based on when, or who, grades the diamond. This is why the same diamond can go to the same lab and receive different grades – quite possibly even from the same individual grader! EGL even states on the bottom of each cert that "Diamond grading is NOT an exact science and this report represents only the best professional OPINION of this company" If it is just the opinion of one gemologist, why should it be so important?

The important thing to realize is that NOT all diamonds with the same grade are equal! If you look on the web for diamond prices you will find that the prices on a 1ct G SI1 can range from approx $5,000 to $10,000. Why is that??  If every G colored SI1 clarity was the same, then people would always buy the cheapest! 

A good SI1 just might be better than a bad VS2!

You should ALWAYS Look at the Diamond, not the Paper certificate!  After all, you are not going to wear the paper on your finger. We have seen many instances where a cheaper priced diamond is the brighter and better appearing stone that more expensive similar sized stones.  What your eye sees and what’s discernable in a lab under a microscope are entirely different values. 

 LOOK AT THE STONE – then make your buying decision!!!

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Summer fashion colors

National Jeweler Magazine reports that blue and green colored gemstones seem to be the up and coming fashion colors for the 2011 summer season.  These hues first appeared at New York’s fashion week earlier this year, and were prevalent on the red carpet for 2011 awards shows.

There are many shades of both blue and green gemstones available, ranging from light colored aquamarine blue to deep-toned Australian sapphire.  In green shades the color range can span from pale peridot green, to dark green Brazilian tourmalines. 

Many of the gems in these colors are relative inexpensive, allowing for larger gems to be used in the construction of custom ordered pieces. Also, in keeping with trends seen over that past several years, the mixing of colors is quite common, and a good designer or individual with some artistic flair can easily find shades of blue and green gems which complement one another for use in a custom piece.

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Tucson 2011

Next week marks the opening date of Tucson"s major gems, including the AGTA, GJX and the Holidome shows.  We will be in attendance seeking out new sources for inventory, and renewing relationships with key vendors from prior years. 

If you have any unique gem needs this is likely your best chance to have our people source out the product to fill that need.  Give us a call, or send some electronic correspondence describing the items you are seeking, and we will put it on our shopping list.  Time is short, so don't delay.

Specific Gravity and Refractive Index

As a buyer of gemstones, you will eventually hear the terms ‘specific gravity’ and ‘refractive index’.  Don’t feel overwhelmed!  These terms are much more simple than they sound.  They are just tools to help distinguish between different types of stones.  To explain, we will use Walter Schumann’s Gemstones of the World to help us.  First up: specific gravity.  Specific gravity is the weight of a particular material compared to the weight of the same amount of water.  Therefore, a gem with a specific gravity of 2.6 (quartz) will weigh 2.6 times as much as the equivalent amount of water.  Specific gravity of gemstones always lies between 1 and 7 (for a few references - diamonds are generally 3.47-3.55; rubies are between 3.97 and 4.08; and emeralds are between 2.67 and 2.78).  Let’s say you find an unknown red gem.  Upon performing a specific gravity test, you find the specific gravity to be 4.01.  A quick glance at a reference chart will tell you that you may indeed have a ruby! 

          “Refractive Index” is another way distinguish between different gems.  The technical definition, by Schumann: “[refraction] occurs when a ray of light leaves one medium (e.g. air) and enters obliquely into another medium (e.g. a gem) at the interface between the two mediums.”  Think about a glass of water with a straw in it.  When you look at it, the straw appears to be “bent” where the water and air meet.  This is a perfect example of light refraction.  “Refractive Index” is measured using the speed of light in air divided by the speed of light in the medium.  Different mediums have different speeds of light.  In air, for example, light travels at about 300,000 km/s.  Diamonds, however, slow light down to about 125,000 km/s.  Therefore, the refractive index of a diamond would be 300,000/125,000 = 2.4.  Each medium has it’s own refractive index.  Therefore, with the aid of a tool called a Refractometer, it is easy to determine the type of gemstone simply by its refractive index.  Sapphires, for example, have a RI of about 1.77.  Amethysts have an RI of about 1.55.  By learning the refractive index of an unidentified gem, you can get an idea what type of stone it may be.

Thanks for reading - if you have any questions please don't hesitate to leave a comment!

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So you want to invest in gems…

Frequently we are asked about how to invest in gemstones.  Our standard answer is that same way as you would invest in any other commodity –buy it cheap and sell it for more than your cost.  This is often not so simple of a task. 

Here at NEGS we have been reasonably successful at buying product at attractive wholesale prices.  Typically we accomplish this by going overseas and dealing directly with mining operators or cutting factories.  We also buy in quantity. 

The second half of that investment strategy is to sell for more that it cost.  For us that involves having an office and staff, doing several trade show a year, and offering value added service such as building jewelry to hold you gemstone.  For us, this is a full time business, taking 40+ hours a week if we’re lucky.

If you want to try you hand at making money dealing in gems. We offer this advice.  Concerning buying, your lowest prices will likely be offered by wholesalers and not from retail stores. In addition, you will get a better price by purchasing lots of stones rather than single stones.

You may also be able to run across gems at tag sales or flea markets, pawnshops and estate sales. Sometimes you can find gems considerably below current values. However, you must have the expertise to identify gems, be able to distinguish between natural and synthetic stones, and be prepared to do a lot of legwork.

Selling the gems for a profit is the second, and more difficult part of this process. Jewelry stores are a possible place to sell your gems, as are auction houses and online auctions. Note that, unless you own a business, you are not likely to get a retail price.  If you have weak sales skills, you should not invest in gems.

One last point of warning, if someone tells you a specific gem is a good investment, and that individual does not have a Series Seven License and is a registered investment advisor, they are in violation of The Securities and Exchange Commission laws, and subject to arrest. 

Buy your gems to own and enjoy.  Buy quality, buy at competitive prices.  Hopefully, when you want to sell your gems you will be able to find a willing buyer and make a buck.  However, if you want to make a real living in this trade, expect that it will probably only happen if you turn this hobby into a full time job.  Good luck.
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Colored Stone Shapes

Colored gemstones are cut into may varied geometric shapes.  Many of these shapes have names that clearly indicate the gem’s shape, such as round, oval, pear, square and heart cuts.  However, some of the other cuts  have names not so indicative of the finished shape of the gem.

 I’ll try to define some of the more common shapes in this blog.  These descriptions are what you would see if you were looking straight down at the top of a colored gemstone.

Marquise Cut    This is basically a two sided stone – kind of  a football shaped gem.  The industry standardized proportions call for the finished gem’s length to be 2 times the width – 4mm X 8mm, or 6mm X 12mm and so on.

Emerald Cut     Is an octagon shaped gem.  Is easiest to describe this shape as a rectangle with the four corners slightly cut off at a 45-degree angle.  This benefit of this rectangle with the corners nipped off is that the pointed 90-degree corners on a rectangle are a weak area, and, especially with emeralds, are prone to breaking

Cushion Cut    If you were to take an emerald cut (described above), and round off the four corners as well as cut a slight curve shape to the four longer sides, you would have a cushion cut.  This shape gets its name from the shape of an overstuffed pillow, or cushion you might find resting on a home sofa.  A cushion cut gem that is about the same length and width is commonly referred to as an antique cushion cut.

Trillion Cut     This is a three sided gem, with all sided being equal in length.  This shape is often used as a pair of matching gems set to each side of a larger center stone.  When a trillion is larger in size it is often used as a pendant stone, but this shape is an excellent choice for a designer ring.

Cabochon Cut    When any shape of a gem is just domed with a convex top and a flat bottom.  The name comes from the Middle French word caboche meaning head. Cab cut stones are usually, but not always opaque gems, while faceting is usually applied to transparent stones.


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Avoid Marange Diamonds

Avi Paz, the president of the World Federation of Diamond Bourses (WFDB) has issued a strongly worded recommendation to the jewelry industry: Don't buy Marange rough.  Paz has indicated that diamonds from the Marange diamond fields in Zimbabwe--a troubled region that is the site of alleged, widespread human rights abuses--should not be purchased until approved by the Kimberley Process (KP) Working Group.  The KP Group was founded in response to the "conflict diamond" being sold during the mid 2000's.  

There are many diamonds being mined in KP approved areas where human rights are being respected.  The miners in these areas rely on the diamond industry to make a decent living wage, and we at NEGS promise to only offer for sale those diamonds which have passed through the KP Process.
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Pearl Shopping

Pearl is the most commonly accepted birthstone for the month of June.  While a pearl is not actually a stone, the use of pearls in jewelry has a storied history as long as that of many precious gemstones, and pearls are widely accepted as a precious jewelry item much like a ruby, sapphire or diamond.  Here is a little info to help you better understand exactly what is available for purchase in the pearl industry.

First, real pearls (as opposed to synthetic of simulated pearls) come in two major categories, cultured and natural.  A natural pearl can only be formed in a wild oyster (mussel) that is living in its natural habitat. A natural pearl is formed without human intervention.  A cultured pearl is formed when a pearl farmer places a foreign substance in an oyster, and keeps the oyster in a confined farm area.

Irregular shaped pearls can be a natural pearl, or a keshi pearl. Keshi pearls are formed when the oyster spits out the human implanted nucleus before the culturing process is complete. Keshi pearls come from both saltwater and freshwater environments. Keshis are generally small in size.  Natural pearls are also rarely round in shape because there was no round shaped nucleus implanted to help shape the finished pearl. Keshis come in a wide variety of colors.  They tend to have high luster and orient due to their solid nacre composition.

Japan has long been the leading producer of akoya pearls, which are round pearls cultured in an Akoya oyster. For over 100 years Japanese akoya pearls have been known for their high quality. Recently Akoya oysters have been transplanted to several other nations, and Akoya pearls can now be produced in these non-Japanese locations. Hence,the phrase "Japanese Akoyas" is no longer used, since most pearl strands can combine both Chinese and Japanese Akoyas.

In fact, the trade consensus is that it doesn't matter where Akoyas are cultured as long as their quality is high. This larger production as helped control and even lower prices, and this is great for the retail pearl buyer.  Happy pearl shopping...

Pearl phot linked from:
  http://www.pbs.org/wgbh/nova/pearl/oysters.html
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Treated and Composite Rubies

Recently there have been TV reports on retail stores selling composite rubies.  A composite ruby is not the same thing as a treated ruby.  For generations rubies have been treated, usually with heat, to improve their color.  This process is well known and accepted within the jewelry industry. If fact, heated rubies are so common that  it's relatively safe to assume that any ruby you are considering purchasing has been heated.  If it has not been heated there almost certainly will be a certificate from a gem lab indicating the stone is natural.

During heating there is often some level of  minor glass residues found in surface-reaching cracks. This glass is the bi-product of the borax coating given the stone for its protection during the heating process.

Glass, or some other type of filling can be used specifically to fill in or minimize the appearance of  surface reaching cracks in an otherwise beautiful ruby.  If that treatment process has taken place the gem should be described as being glass filled.  This filling process will also be noted on a lab report.

All these treatments are required by law to be disclosed by the seller. But these types of treatments should not be confused with a "composite ruby".  Composite stones are created from multiple pieces of low-quality corundum which has been molded together with tinted glass.   These composite stones have no place in the jewelry industry, and should not sold by any reputable jeweler.

For additional info on this topic there is a terrific article written by the AGA which describes ruby treatments and composite (junk) rubies.   Link to that Ruby article here.

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Diamond Pricing Trends Moving Up

Industry sources claim that over the month of March wholesale diamond prices rose sharply.   FYI, diamond prices peaked in August 2008, and then fell quickly along with the decline in housing and financial markets late that year.  Prices reached a low during early 2009, and stayed low for most of that year.  Near late 2009, early 2010 wholesale diamond prices started to move up, and that trend has continued. 

That rise in wholesale price is now just beginning to be felt at the retail store level, so be prepared to experience sticker shock if you shopped diamonds last year but did not purchase, as the price you may have been quoted then is now likely gone only to be replaced with higher numbers.

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Christie's April 22 Auction

Christie's Auction Gallery announced they will be auction two significant pieces of antique, historical jewelry on April 22.  The pieces are  The Catherine the Great Emerald ,and The Emperor Maximilian Diamond.


The emerald was mounted as a broach for Catherine II of Russia. The stone weighs approximately 65 carats, and is accented with rose and old mine-cut diamonds. The estimated price for this little piece is $1 to $1.5 million. 

The diamond piece is a cushion-cut gem weighing approximately 39.55 carats. The stone was once owned by Emperor Maximilian of Mexico.  The early estimate of auction price is also $1 to $1.5 million.

Christie's Auction Catalog

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Mexico's Cave of Crystals

Mexico's Cave of Crystals stunned geologists when it was first discovered in 2000. The underground chamber contains some of the largest natural crystals ever found.  Britain's Professor Iain Stewart got a rare glimpse of the subterranean spectacle while filming for the new BBC series How the Earth Made Us.  Check out the BBC video clip on this link.
http://news.bbc.co.uk/2/hi/science/nature/8466493.stm

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Grams & Millimeters Translated

The jewelry trade, and many others, typically measure items in millimeters, grams, and carats.  Jewelers toss these terms around as if everyone was completely comfortable with the metric system of measurements.

To help put these measurements into a context everyone understands, lets measure some common, everyday items using the metric system.  These lengths and weights are only close approximations of actual weights or lengths, but close enough to allow you to visualize what  a millimeter or a gram represents.

•      copy paper                   measures              1/10 mm thick
•      10 piece copy paper     measures              1 mm thick
•      1 inch                           measures              25 mm
•      #2 lead pencil               measures              7 mm diameter
•      a dime                          measures              18 mm diameter
•      USB plug                     measures               4.5 X 12 mm  W x L
•      dollar bill                      measure                65 X 150 mm  W x L
•      dollar bill                      weighs                  1 gram
•      dollar bill                      weighs                  5 carats
•      a nickle                        weighs                  5 grams

If someone throws out the term "pennyweight" instead of gram, one pennyweight (abbreviated DWT) is about 1.5 grams.  Grams are often used for weighing fabricated, or built jewelry, while pennyweight is commonly used for the weight of a cast piece.

There are five carats in one gram, and 100 points in one carat.  A 25 point diamond is 1/4 carat.

   
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Separate Diamond from Cubic Zirconia

Cubic Zirconia (CZ) can easily be confused with diamonds.  It's possible that diamond you're considering buying from an online auction or picking up from a "friend" just might be a CZ.  Jewelers usually separate CZs from diamonds by using a relative inexpensive tool called a  thermal probe.  However, it's unlikely the average retail consumer will want to spend a few hundred dollars to buy one of these probes just to identify one stone.  For the person on the street it’s helpful to know the a few of the key clues a jeweler might use to identify a CZ.

 
First, CZ has a much higher specific gravity than diamond: 5.80 vs. 3.52. This means a loose CZ will feel unusually heavy. 

 
Second, with magnification polished CZs will show some obvious differences. The faceting is rarely as precise as with diamond, and the girdle will likely have a rough polished appearance, unlike the grainy or faceted girdles you’ll see on a diamond. 

Third, when viewed with a small light from the backside, CZ will show a monochromatic orange flash on the pavilion or pointed side; diamonds usually shows a mix of colors.

Forth, when a diamond is placed table side down on a lined piece of paper, the printed line which is directly underneath of the stone is not visible because diamonds will USUALLY reflect the line's image away from the viewer.  Not so with a CZ.

These tests may not be definitive, and if you are in doubt the stones true identity, it's best consult with you local jeweler just to make sure. 

This information is largely taken from the GIA's Diamond ID and Grading courses.

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American Idol Show Showcases Yellow Gold Jewelry

Viewers of this week's American Idol may have noticed that gold jewelry was being widely worn by all the remaining female contestants.  Showcased were yellow gold earrings, bracelets and necklaces.  The use of yellow gold is noteworthy as it is another indicator that white gold is beginning to decline in popularity.

American Idol stylist Soyon An worked with Studio PR and the World Gold Council to wardrobe the contestants in gold jewelry. "It really showed that these young stars can wear gold jewelry and that it is fashionable at any age," Studio PR's Shaye Strager told National Jeweler Magazine.

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Diamond Color Grades Explained

Diamond color grades are not that hard to understand.  Most jewelry shoppers know the color of a diamond is identified by a letter of the alphabet, with "D" representing the top color.  More accurately, “D” represents the total absence of color, and stones that exhibit a slightly more tinted color are graded E, F, G and on down the alphabet.  But what exactly does that letter grade represent, and what's the difference between a "D" and an "E colored stone. 


If you have ever been in a big box hardware store's paint department you have likely seen one of those large racks of paint color chips - you know, those little pieces of colored paper which show the various colors of paint available for purchase.  If you look at the whitest of white paint chips, then select the next five or so progressively less white chips, that small selection of colors of similar colors could be defined as representing the color range of "D" color graded diamonds.  The next five or so slightly darker tinted chips might be considered as representing an "E", the next five chips or so a "F", and so on.

The difference between two color grades of diamonds could be defined as the observed color difference between the top level color of  one grade range, and the top level color of an adjacent color grade range.  It is noteworthy that a particular letter color grade is not a specific point on the color wheel, but a small, narrowly defined range of very similar colors. 

When you purchase a graded color diamond you really don't know if your "E" color is just short of being graded a "D" color, or if your selected stone just missed being graded a "F" color.  This range of colors within a listed grade is one of several reasons why stones that are graded the same are not often priced the same.  A top level "E and bottom level "E" colored diamond are not priced the priced the same at the wholesale level, and that price differential is reflected in their retail selling price.

 
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Diamond Certificates

We are frequently asked about the differences in diamond grading labs.  Here is the results of an industry analysis of the more common grading labs.  REMEMBER, look at the diamond carefully to see if it it is suitable for your needs and pocketbook, the certification paper is only someone's opinion of how they would grade the stone.

Myth and Facts

• “Diamonds graded by GIA-GTL have better resale liquidity”. Fact
• "GIA is the strictest laboratory in the world" – Myth. According to this survey 8 out of 16 diamonds were graded more strictly by AGS. EGL tended to grade clarity more strictly.
• "AGS is very strict" – A fact overall, but AGSL color grades can be softer than GIA-GTL.
• "EGL certificates are not worth the paper they are printed on" – Myth. Although in 12 cases out of 17 EGL graded color softer, EGL clarity grading was as strict or stricter as GIA.
• "GIA has the strongest international diamond brand" - Fact.
• "It is safer to buy a GIA graded diamond" - Myth. Any diamond grading report is an opinion, not a guarantee.

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Cullinan Heritage Diamond sells for $35.3 Million

As reported in National Jeweler's online  Magaine.  Petra Diamonds Ltd. announced the sale of a 507-carat rough diamond unearthed at its Cullinan mine.  The stone sold for $35.3 million, the highest sale price on record ever achieved for a rough diamond.

Hong Kong-based Chow Tai Fook Jewellery Company Ltd. bought the hefty piece of rough, dubbed the "Cullinan Heritage," at a tender in South Africa. At 507.5 carats, the Cullinan Heritage is the 19th largest piece of rough unearthed in history, and it is one of many important diamonds to come out of the South African Cullinan mine, which was once owned by De Beers.

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