Diamonds are made out of carbon—highly organized carbon, that is. Geologists are still guessing how diamonds formed in the Earth from 1 billion to 3 billion years ago, according to a recent study in the journal Nature, but they think the recipe follows something like this:
1. Bury carbon dioxide 100 miles into Earth. 2. Heat to about 2,200 degrees Fahrenheit. 3. Squeeze under pressure of 725,000 pounds per square inch. 4. Quickly rush towards Earth’s surface to cool.
If the process sounds a little difficult, thank a synthetic diamond manufacturer: There are now two ways to make diamonds in the laboratory.
The first synthetic method is called high pressure, high temperature (HPHT for short). It’s the closest thing to the diamond-producing bowels of the Earth, subjecting graphite (yes, the stuff in a No. 2 pencil, which is made from pure carbon) to intense pressure and heat. Tiny anvils in an HPHT machine squeeze down on the graphite as intense electricity zaps it, producing a gem-quality diamond in just a few days. These diamonds, however, aren’t as pure as natural diamonds because a metallic solution is mixed in with the graphite.
The other diamond-producing method—called chemical vapor deposition—turns its back on intense pressure but cranks out diamonds more flawless than nature can produce. Manufacturers place a piece of diamond into a depressurizing chamber, then zap natural gas with a microwave beam. As the gas is heated to almost 2,000 degrees, carbon atoms “rain” down onto the diamond in the chamber and stick to it, growing a perfect sheet of diamond overnight.
Friday, May 8, 2009
screts to keep your diamond sparkling
Diamond is the hardest natural substance on Earth. It can cut any kind of rock or metal, but only another diamond can cut a diamond. In fact, a diamond must be heated to a temperature of 1292 degrees Fahrenheit before it will burn. Yet the oil deposited from the mere touch of a human finger can cause dirt to collect and make this nearly indestructible gemstone quickly lose its sparkling appeal.
So how can you keep your diamond looking its very best? The nonprofit Gemological Institute of America (GIA) – regarded as the world’s foremost authority in gemology – offers the following tips on diamond care:
Handle your diamond sparingly. Because diamonds are natural magnets for grease, they’re not easy to keep clean. Handling a diamond with your fingers provides enough oils from your skin (the type of “grease” that most affects diamonds) to alter the way your diamond looks.
Clean your diamond regularly. A simple plan to keep your diamond jewelry always looking beautiful is to soak the diamond in an ammonia-based household cleaner (such as window cleaner) overnight, once or twice weekly. In the morning, remove the diamond from the cleaner and brush it with a soft, clean toothbrush (one that has not previously been used in any way, and that you reserve exclusively for cleaning your diamond) to remove any leftover dirt. Take extra care to brush the back of the diamond as this will be the area that has collected the most oil and dirt.
Be aware that fragile settings and estate jewelry won’t take kindly to being scrubbed with a toothbrush, so use a soft touch. Then, just rinse the diamond with water and wipe with a soft, lint-free cloth.
Don’t use harmful solutions. Chlorine (as in household bleach) or abrasives (such as household cleansers or toothpaste) should never be used when cleaning diamonds, especially those set in jewelry. These erode some of the metals often used in diamond settings, and may loosen prongs, or even dissolve the metal completely.
Sometimes an ultrasonic cleaner is necessary to remove encrusted dirt on diamonds. By sending high frequency sound waves through a detergent solution, ultrasonic cleaners cause vibrating fluid to remove accumulated dirt and grime. However, they can also shake loose stones from their mounting, so this method shouldn’t be used on fragile settings (or estate jewelry), and is best undertaken by a professional jeweler.
Regular cleaning will keep your diamond jewelry in gleaming condition and ready to sparkle on that special occasion.
So how can you keep your diamond looking its very best? The nonprofit Gemological Institute of America (GIA) – regarded as the world’s foremost authority in gemology – offers the following tips on diamond care:
Handle your diamond sparingly. Because diamonds are natural magnets for grease, they’re not easy to keep clean. Handling a diamond with your fingers provides enough oils from your skin (the type of “grease” that most affects diamonds) to alter the way your diamond looks.
Clean your diamond regularly. A simple plan to keep your diamond jewelry always looking beautiful is to soak the diamond in an ammonia-based household cleaner (such as window cleaner) overnight, once or twice weekly. In the morning, remove the diamond from the cleaner and brush it with a soft, clean toothbrush (one that has not previously been used in any way, and that you reserve exclusively for cleaning your diamond) to remove any leftover dirt. Take extra care to brush the back of the diamond as this will be the area that has collected the most oil and dirt.
Be aware that fragile settings and estate jewelry won’t take kindly to being scrubbed with a toothbrush, so use a soft touch. Then, just rinse the diamond with water and wipe with a soft, lint-free cloth.
Don’t use harmful solutions. Chlorine (as in household bleach) or abrasives (such as household cleansers or toothpaste) should never be used when cleaning diamonds, especially those set in jewelry. These erode some of the metals often used in diamond settings, and may loosen prongs, or even dissolve the metal completely.
Sometimes an ultrasonic cleaner is necessary to remove encrusted dirt on diamonds. By sending high frequency sound waves through a detergent solution, ultrasonic cleaners cause vibrating fluid to remove accumulated dirt and grime. However, they can also shake loose stones from their mounting, so this method shouldn’t be used on fragile settings (or estate jewelry), and is best undertaken by a professional jeweler.
Regular cleaning will keep your diamond jewelry in gleaming condition and ready to sparkle on that special occasion.
Ideal Diamonds
Ideal Diamonds (Characteristics)
Yes, there are certain distinguishing characteristics that IDEAL cuts have.Firstly, on an 'ideal cut' if you look directly down and straight into the table of the diamond with a 10X loupe you will notice a certain phenomenon. Focus towards the bottom point of the diamond (the culet) and you should notice a small octagonal formation around the culet (point on the bottom of the diamond). This is a reflection that can be observed in diamonds that are not deeply cut. This image should extend about 1/5 to 1/3 of the table diameter. The size of this sort of circle, shows the pavilion depth of the stone.The larger this circle the deeper the stone is.
To achieve maximum brilliancy in a diamond it is essential that the facets be flat, planar surfaces. Hasty and careless polishing can leave wheel marks that affect brilliancy and luster. These wheelmarks are seldom visible to the unaided eye. The wheel marks cause the surface to be very minutely grooved, and in turn these minute grooves caused diffusion of the light that is transmitted through and reflected from the diamond. A well polished diamond will show no evidence of wheel marks under 10X. Wheel marks can easily reduce the brilliancy of a diamond to below its optimum beauty.
The machines that measure facet percentages and angle at his time only report one angle, but future technology is going to address facet yaw, and address the aspects of a three dimensional item
GIRDLE:
The foundation of the diamond is directly relevant to how well the girdle is created.
Preferably, the girdle should be faceted or polished, and the most uniform in thickness. Be aware that the variance of thickness affects the facets cut and polished near the girdle. If the girdle varies then the facets will vary. This really isn’t that noticeable to the eye, but if you really want super precision in the cut, it a consideration that shouldn’t be omitted.
The girdle of diamonds can range from extremely thin to extremely thick. This applies to both GIA and AGS graded diamonds. Avoid diamonds with extremely thin or thick girdles. Extremely thin girdles can be chipped easier than ones that are thicker, and very thick or extremely thick girdles can detract from the appearance of the diamond.
A well finished girdle surface is one that is so smooth that appears similar to the other facets, a glassy appearance.
If a diamond is rounded up too quickly in the fashioning process, the result will be a fuzzy appearing girdle that may be rough. A rough girdle may make a diamond appear greyer or darker when viewed face up. This would be caused by oil or dirt becoming embedded in the girdle surface.
”A girdle may be faceted or polished and this has no effect on the value of the diamond, unless it appears unattractive.
Careful and precise girdling also results is a “rounder” stone. Not the minimum diameter measurement and the maximum measurement on a GIA or AGS report. Find a diamond with the same minimum and maximum measurements of the diameteris uncommon as the equipment used is capable of producing a perfectly round girdle. Most diamonds have a small variance in the measurements, but there are some that are so far apart that the stone may appear out of round to the naked eye.
CULET:
The culet should appear as a tiny polished facet at the tip of the pavilion. Should the culet be chipped or abraded, this will detract from the diamond's appearance. If the culet is rough or unpolished, it will appear as a frosty white dot. In a finely cut diamond, the culet should be either pointed, very small, small or medium.
The culet should also be centered as much as possible. This is particularly important in fancy shaped stones, such as the Princess cut. Stones that have an off center culet generally have lopsided pavilions. This isn’t reported on most lab reports, but is on the advanced Sarin reports.
SYMMETRY:
Symmetry discrepancies should not be visible under 10X if a diamond is to be considered well cut. The table must conform to the ideal octagonal shape. The facets should all meet at a point and if they fail to do so they would be misshapen as a result. When a diamond is graded for symmetry, the following 8 features are taken into account.
1.) Table or culet slightly off centre.2.) Unequal sizes of opposing facets.3.) Misshapen facets.4.) Table not octagonal.5.) Girdle outline slightly out of round.6.) Table not parallel to girdle.7.) Facets fail to point up.8.) Pavilion and crown main facets out of alignment.
Yes, there are certain distinguishing characteristics that IDEAL cuts have.Firstly, on an 'ideal cut' if you look directly down and straight into the table of the diamond with a 10X loupe you will notice a certain phenomenon. Focus towards the bottom point of the diamond (the culet) and you should notice a small octagonal formation around the culet (point on the bottom of the diamond). This is a reflection that can be observed in diamonds that are not deeply cut. This image should extend about 1/5 to 1/3 of the table diameter. The size of this sort of circle, shows the pavilion depth of the stone.The larger this circle the deeper the stone is.
To achieve maximum brilliancy in a diamond it is essential that the facets be flat, planar surfaces. Hasty and careless polishing can leave wheel marks that affect brilliancy and luster. These wheelmarks are seldom visible to the unaided eye. The wheel marks cause the surface to be very minutely grooved, and in turn these minute grooves caused diffusion of the light that is transmitted through and reflected from the diamond. A well polished diamond will show no evidence of wheel marks under 10X. Wheel marks can easily reduce the brilliancy of a diamond to below its optimum beauty.
The machines that measure facet percentages and angle at his time only report one angle, but future technology is going to address facet yaw, and address the aspects of a three dimensional item
GIRDLE:
The foundation of the diamond is directly relevant to how well the girdle is created.
Preferably, the girdle should be faceted or polished, and the most uniform in thickness. Be aware that the variance of thickness affects the facets cut and polished near the girdle. If the girdle varies then the facets will vary. This really isn’t that noticeable to the eye, but if you really want super precision in the cut, it a consideration that shouldn’t be omitted.
The girdle of diamonds can range from extremely thin to extremely thick. This applies to both GIA and AGS graded diamonds. Avoid diamonds with extremely thin or thick girdles. Extremely thin girdles can be chipped easier than ones that are thicker, and very thick or extremely thick girdles can detract from the appearance of the diamond.
A well finished girdle surface is one that is so smooth that appears similar to the other facets, a glassy appearance.
If a diamond is rounded up too quickly in the fashioning process, the result will be a fuzzy appearing girdle that may be rough. A rough girdle may make a diamond appear greyer or darker when viewed face up. This would be caused by oil or dirt becoming embedded in the girdle surface.
”A girdle may be faceted or polished and this has no effect on the value of the diamond, unless it appears unattractive.
Careful and precise girdling also results is a “rounder” stone. Not the minimum diameter measurement and the maximum measurement on a GIA or AGS report. Find a diamond with the same minimum and maximum measurements of the diameteris uncommon as the equipment used is capable of producing a perfectly round girdle. Most diamonds have a small variance in the measurements, but there are some that are so far apart that the stone may appear out of round to the naked eye.
CULET:
The culet should appear as a tiny polished facet at the tip of the pavilion. Should the culet be chipped or abraded, this will detract from the diamond's appearance. If the culet is rough or unpolished, it will appear as a frosty white dot. In a finely cut diamond, the culet should be either pointed, very small, small or medium.
The culet should also be centered as much as possible. This is particularly important in fancy shaped stones, such as the Princess cut. Stones that have an off center culet generally have lopsided pavilions. This isn’t reported on most lab reports, but is on the advanced Sarin reports.
SYMMETRY:
Symmetry discrepancies should not be visible under 10X if a diamond is to be considered well cut. The table must conform to the ideal octagonal shape. The facets should all meet at a point and if they fail to do so they would be misshapen as a result. When a diamond is graded for symmetry, the following 8 features are taken into account.
1.) Table or culet slightly off centre.2.) Unequal sizes of opposing facets.3.) Misshapen facets.4.) Table not octagonal.5.) Girdle outline slightly out of round.6.) Table not parallel to girdle.7.) Facets fail to point up.8.) Pavilion and crown main facets out of alignment.
What Makes A Diamond So Special
The word alone conjures up a thousand images: rare, precious, desirable, beautiful, sparkling tokens of love. Created deep within the core of the earth more than 100 million years ago and brought to the surface by volcanic eruption, most of the diamonds sparkling on fingers today are more than 100 million years old!
Even before these magnificent creations of nature were mined in profusion toward the end of the 19th century, they were a source of fascination and value to early man. The Romans thought diamonds were splinters from falling stars, while the Greeks regarded the sparkling gems as tears of the gods. It is a derivation of the Greek word "adamas," meaning unconquerable, that gave the diamond its name.
Rare and fascinating, mysterious and magical, the diamond has ignited romantic passion throughout history.
The diamond claimed its place as the primary token of love toward the end of the 15th century, when Austrian Archduke Maximilian gave the first diamond engagement ring to his betrothed. It was placed on the fourth finger of her left hand, because that finger was believed to course with the vein of love that passed directly to the heart. Five centuries later, the diamond remains one of the most luxurious and desirable gifts for any romantic and celebratory occasion, a gem whose purity and brilliance symbolizes lasting love.
What Makes a Diamond Special?
Beauty - The colorless beauty and inner fire of the diamond has made this precious gem prized for centuries. Each stone's complex characteristics cannot be duplicated, and no two diamonds can ever be the same. Each stone, like its owner, is endowed with a personality and character uniquely its own.
Durability - A diamond is the hardest substance known to man, making it resistant to deterioration. When cared for properly, diamond jewelry can be worn every day and passed on as an heirloom to the next generation.
Purity - Although new resources for diamonds are being explored and discovered, the supply of these gems remains limited. This is understandable once you learn that more than 250 tons of ore need to be blasted, crushed and processed to yield just one carat of rough diamond. Further, only 20 percent of all rough diamonds are suitable for gem cutting.
Enduring Value - Like many precious products, diamond prices fluctuate. But it is important to know that these sparkling gemstones still retain value after years of being worn and enjoyed.
Even before these magnificent creations of nature were mined in profusion toward the end of the 19th century, they were a source of fascination and value to early man. The Romans thought diamonds were splinters from falling stars, while the Greeks regarded the sparkling gems as tears of the gods. It is a derivation of the Greek word "adamas," meaning unconquerable, that gave the diamond its name.
Rare and fascinating, mysterious and magical, the diamond has ignited romantic passion throughout history.
The diamond claimed its place as the primary token of love toward the end of the 15th century, when Austrian Archduke Maximilian gave the first diamond engagement ring to his betrothed. It was placed on the fourth finger of her left hand, because that finger was believed to course with the vein of love that passed directly to the heart. Five centuries later, the diamond remains one of the most luxurious and desirable gifts for any romantic and celebratory occasion, a gem whose purity and brilliance symbolizes lasting love.
What Makes a Diamond Special?
Beauty - The colorless beauty and inner fire of the diamond has made this precious gem prized for centuries. Each stone's complex characteristics cannot be duplicated, and no two diamonds can ever be the same. Each stone, like its owner, is endowed with a personality and character uniquely its own.
Durability - A diamond is the hardest substance known to man, making it resistant to deterioration. When cared for properly, diamond jewelry can be worn every day and passed on as an heirloom to the next generation.
Purity - Although new resources for diamonds are being explored and discovered, the supply of these gems remains limited. This is understandable once you learn that more than 250 tons of ore need to be blasted, crushed and processed to yield just one carat of rough diamond. Further, only 20 percent of all rough diamonds are suitable for gem cutting.
Enduring Value - Like many precious products, diamond prices fluctuate. But it is important to know that these sparkling gemstones still retain value after years of being worn and enjoyed.
Diamond Market
There are fewer than 200 or so companies or people authorized to buy these rough diamonds from De Beers. These “sightholders” tend to meet in Antwerp, Israel, London, and New York. They trade under the organizations of “The Syndicate”, “Central Selling Organization”, “Diamond Trading Company”, “Antwerp World Diamond Center” where these sightholders will sit across from each other and haggle ( to argue in bargaining ) on the numerous rough, polished and industrial diamonds through a formal contract of a simple handshake with the words “Muzel” exchanged.
Diamonds are the most coveted of all precious gems, as is witnessed by the extremely high demand for them. While this has not always been the case, diamonds are nonetheless exquisite gems that go through a long, tedious refining process from the time they are pulled from the ground to when you see them in the jewelry store. And, while some of the mystique of diamonds may be gone -- they're just carbon, after all -- the diamond will likely continue to be a highly coveted jewel, because, well, "A Diamond is Forever."
Diamonds are the most coveted of all precious gems, as is witnessed by the extremely high demand for them. While this has not always been the case, diamonds are nonetheless exquisite gems that go through a long, tedious refining process from the time they are pulled from the ground to when you see them in the jewelry store. And, while some of the mystique of diamonds may be gone -- they're just carbon, after all -- the diamond will likely continue to be a highly coveted jewel, because, well, "A Diamond is Forever."
How Clarity is graded
Vision varies from person to person. What one person can see with the unaided eye, another one can’t see. They same goes for examination under 10 power.
Most consumers think that graded under 10 X magnification means that the grader looked only at 10 X. This is not true. When examining a diamond the grader can increase the magnification until he finds all the inclusions. Once an inclusion is seen at whatever power, the grader then looks for that inclusion at 10x to see if it can still be observed. If so, the inclusion is considered when determining a clarity grading.
The stone is examined in a multitude of positions. Clarity grading is determined only in the face up position.
In order to properly examine a diamond’s clarity, it is necessary to examine it using dark field illumination. Looking at a diamond without dark field illumination is invalid as some inclusions might not be visible, and thus not an accurate method of clarity grading.
Before we determine the description of each clarity grade, readers should be aware that the major labs ( GIA, AGS etc.) are more “forgiving” in assigning clarity grades for stone that weigh more than 1.50 carats.
Diamonds that are step cut , such as the Emerald Cut or Asscher will show inclusions easier than rounds or stones with other styles of pavilion (underside) faceting.
Standards of Clarity Grading
The standards listed below are for GIA grading ONLY. Some labs such as IGI and EGL have different standards. It is the author’s opinion that unless the GIA standards are adhered to, the consumer assumes that an EGL SI-2 stone is equal to an SI-2 clarity graded stone from GIA.
What makes this more confusing for consumer’s is that all the labs use the GIA nomenclature, even when their standards are different. It is the author’s opinion that if a lab doesn’t adhere to the standards of GIA, the terminology should be different. However, it isn’t.
For example IGI and EGL use the grade of SI-3. If GIA were to grade a stone graded SI-3 – the result would usually be equal to I-1 in GIA terminology. However, SI-3 was “invented” by these labs, for stones that would be borderline I-1’s.
Preferred Types of Inclusions
The smallest inclusions are the most preferred.
Small inclusions would be
Pinpoints
Needles
Clouds ( clusters or groups of pinpoints)
Wisps
Other inclusions:
Crystals (transparent ones face up)
Feathers - (but not where they are opening on surface of the diamond or at the girdle of the stone) Size also matters too, as well as location in the stone.
Least Preferred Inclusions
Cleavages – These are cracks in the stone which run parallel to the grain of the diamond.
Eye Clean – What does it REALLY mean?
Generally, the clarity grades of VS are usually eye clean. Eye clean means that the diamond does not have visible inclusions to the unaided eye, examined in proper lights, held with the table of the diamond perpendicular to the eye (face up) and a distance of approximately 12-15 inches.
VVS1 & VVS2 CLARITY GRADES
The terms VVS-1, very very small 1, and VVS-2, very very small 2, describe diamonds that when viewed under 10X magnification by an expert show only very, very small inclusions which are difficult to be seen. The inclusions should be light colored. The features of the VVS grade are exceptionally difficult to discern. The typical inclusions of this grade are dot-like inclusions. Whether a diamond is VVS-1 or VVS-2 depends on the relative degree to which the minute inclusions are present. If they are present to a minimal degree then the VVS-1 grade is chosen. Just a little added touch to the degree of inclusions will result in a VVS-2 grade.
VS1 & VS2 CLAITY GRADES
Diamonds are classified into the VS, very small inclusions grade, when the expert using a ten times magnification can discern very small inclusions which are difficult to be seen. The experienced grader does not find the internal faults at once, but does not have too great difficulties to see the inclusions when he moves the diamond a little from side to side. Typical inclusions of this group are small, light clouds or small light cracks on the girdle as well as single crystals just slightly larger than a dot. Inclusions in this clarity grade should be mainly light-colored. Very small dark inclusions are allowable under the girdle. Depending on the degree of inclusions the diamond is either rated VS-1 having fewer inclusions or VS-2 having just a little higher degree of inclusions.
SI1 & SI2 CLARITY GRADES
The SI or 'small inclusions' term comprises diamonds which, when viewed with ten times magnification have small inclusions. These are usually easily seen by an experienced grader. As soon as he observes the diamond with the right magnification the inclusions jump into the field of view and should be light and around the girdle there can be small, dark inclusions. Again, depending on the degree to which inclusions are present the diamond is either rated SI-1 or SI-2, with the SI-1 having a lesser degree of inclusions than an SI-2.
I-1 – I-2 OR (IMPERFECT) CLARITY GRADES
The I-1 (Imperfect-1) grade sometimes is referred to as the P-1 or (Pique'-1) grade. The word pique' is a French word meaning 'mark' or 'spot'. The I-1 grade comprises those diamonds which when viewed with ten times magnification show several inclusions at once but which do not diminish the brilliance. With the naked eye, when viewed through the crown, these faults, even in larger diamonds, are only discernible with difficulty. Typical defects of this group are larger colored inclusions as well as larger cracks or plane-like inclusions. The I-2 (Imperfect-2) or P-2 grade is comprised of diamonds with larger and/ or numerous inclusions which can be seen with the naked eye through the crown and which may diminish the brilliance somewhat even in smaller diamonds. There might be dark inclusions or numerous light-colored features. Another characteristic is larger cracks which may influence the durability of the stone and they could possibly expand under stress into the interior of the diamond, especially if they are to be found near the girdle.
It is not recommended to purchase a diamond with a clarity grade of I-2 or lower since the multitude of inclusions will tend to block or impede the passage of light through the diamond and thus reduce the overall brilliancy. Also, the presence of larger inclusions especially cleavage-like inclusions will create a certain amount of internal strain that will ultimately weaken the diamond.
However, there are to be found large diamonds with an I-2 clarity that seem to be quite brilliant and are quite strong. Ask your independent gemologist his opinion on any I-2 or lower clarity diamond. Ask him specifically about reduced brilliancy and the overall strength of the diamond.
I-3 CLARITY GRADE
The I-3 (Imperfect-3) or P-3( Pique'-3) clarity grade is the lowest grade of clarity and is comprised of large and/ or numerous inclusions which are easily visible through the crown with the naked eye. The number and size of inclusions usually diminish the brilliance considerably.
Most consumers think that graded under 10 X magnification means that the grader looked only at 10 X. This is not true. When examining a diamond the grader can increase the magnification until he finds all the inclusions. Once an inclusion is seen at whatever power, the grader then looks for that inclusion at 10x to see if it can still be observed. If so, the inclusion is considered when determining a clarity grading.
The stone is examined in a multitude of positions. Clarity grading is determined only in the face up position.
In order to properly examine a diamond’s clarity, it is necessary to examine it using dark field illumination. Looking at a diamond without dark field illumination is invalid as some inclusions might not be visible, and thus not an accurate method of clarity grading.
Before we determine the description of each clarity grade, readers should be aware that the major labs ( GIA, AGS etc.) are more “forgiving” in assigning clarity grades for stone that weigh more than 1.50 carats.
Diamonds that are step cut , such as the Emerald Cut or Asscher will show inclusions easier than rounds or stones with other styles of pavilion (underside) faceting.
Standards of Clarity Grading
The standards listed below are for GIA grading ONLY. Some labs such as IGI and EGL have different standards. It is the author’s opinion that unless the GIA standards are adhered to, the consumer assumes that an EGL SI-2 stone is equal to an SI-2 clarity graded stone from GIA.
What makes this more confusing for consumer’s is that all the labs use the GIA nomenclature, even when their standards are different. It is the author’s opinion that if a lab doesn’t adhere to the standards of GIA, the terminology should be different. However, it isn’t.
For example IGI and EGL use the grade of SI-3. If GIA were to grade a stone graded SI-3 – the result would usually be equal to I-1 in GIA terminology. However, SI-3 was “invented” by these labs, for stones that would be borderline I-1’s.
Preferred Types of Inclusions
The smallest inclusions are the most preferred.
Small inclusions would be
Pinpoints
Needles
Clouds ( clusters or groups of pinpoints)
Wisps
Other inclusions:
Crystals (transparent ones face up)
Feathers - (but not where they are opening on surface of the diamond or at the girdle of the stone) Size also matters too, as well as location in the stone.
Least Preferred Inclusions
Cleavages – These are cracks in the stone which run parallel to the grain of the diamond.
Eye Clean – What does it REALLY mean?
Generally, the clarity grades of VS are usually eye clean. Eye clean means that the diamond does not have visible inclusions to the unaided eye, examined in proper lights, held with the table of the diamond perpendicular to the eye (face up) and a distance of approximately 12-15 inches.
VVS1 & VVS2 CLARITY GRADES
The terms VVS-1, very very small 1, and VVS-2, very very small 2, describe diamonds that when viewed under 10X magnification by an expert show only very, very small inclusions which are difficult to be seen. The inclusions should be light colored. The features of the VVS grade are exceptionally difficult to discern. The typical inclusions of this grade are dot-like inclusions. Whether a diamond is VVS-1 or VVS-2 depends on the relative degree to which the minute inclusions are present. If they are present to a minimal degree then the VVS-1 grade is chosen. Just a little added touch to the degree of inclusions will result in a VVS-2 grade.
VS1 & VS2 CLAITY GRADES
Diamonds are classified into the VS, very small inclusions grade, when the expert using a ten times magnification can discern very small inclusions which are difficult to be seen. The experienced grader does not find the internal faults at once, but does not have too great difficulties to see the inclusions when he moves the diamond a little from side to side. Typical inclusions of this group are small, light clouds or small light cracks on the girdle as well as single crystals just slightly larger than a dot. Inclusions in this clarity grade should be mainly light-colored. Very small dark inclusions are allowable under the girdle. Depending on the degree of inclusions the diamond is either rated VS-1 having fewer inclusions or VS-2 having just a little higher degree of inclusions.
SI1 & SI2 CLARITY GRADES
The SI or 'small inclusions' term comprises diamonds which, when viewed with ten times magnification have small inclusions. These are usually easily seen by an experienced grader. As soon as he observes the diamond with the right magnification the inclusions jump into the field of view and should be light and around the girdle there can be small, dark inclusions. Again, depending on the degree to which inclusions are present the diamond is either rated SI-1 or SI-2, with the SI-1 having a lesser degree of inclusions than an SI-2.
I-1 – I-2 OR (IMPERFECT) CLARITY GRADES
The I-1 (Imperfect-1) grade sometimes is referred to as the P-1 or (Pique'-1) grade. The word pique' is a French word meaning 'mark' or 'spot'. The I-1 grade comprises those diamonds which when viewed with ten times magnification show several inclusions at once but which do not diminish the brilliance. With the naked eye, when viewed through the crown, these faults, even in larger diamonds, are only discernible with difficulty. Typical defects of this group are larger colored inclusions as well as larger cracks or plane-like inclusions. The I-2 (Imperfect-2) or P-2 grade is comprised of diamonds with larger and/ or numerous inclusions which can be seen with the naked eye through the crown and which may diminish the brilliance somewhat even in smaller diamonds. There might be dark inclusions or numerous light-colored features. Another characteristic is larger cracks which may influence the durability of the stone and they could possibly expand under stress into the interior of the diamond, especially if they are to be found near the girdle.
It is not recommended to purchase a diamond with a clarity grade of I-2 or lower since the multitude of inclusions will tend to block or impede the passage of light through the diamond and thus reduce the overall brilliancy. Also, the presence of larger inclusions especially cleavage-like inclusions will create a certain amount of internal strain that will ultimately weaken the diamond.
However, there are to be found large diamonds with an I-2 clarity that seem to be quite brilliant and are quite strong. Ask your independent gemologist his opinion on any I-2 or lower clarity diamond. Ask him specifically about reduced brilliancy and the overall strength of the diamond.
I-3 CLARITY GRADE
The I-3 (Imperfect-3) or P-3( Pique'-3) clarity grade is the lowest grade of clarity and is comprised of large and/ or numerous inclusions which are easily visible through the crown with the naked eye. The number and size of inclusions usually diminish the brilliance considerably.
Clarity difference in diamonds
Clarity is sometimes called purity. This terminology varies from grading lab to grading lab.
Let's discuss exactly what each clarity grade means. Diamonds in the flawless category are free from internal and external blemishes when examined by a skilled observer under 10X magnification (see below). Diamonds in the internally flawless category have no internal imperfections but some surface blemishes may be present.
The level of polish blemishes can be ascertained by reading the polish grade on Internally Flawless Clarity graded diamonds. Stones that have Flawless grade must grade Excellent for polish. Flawless graded diamonds are very uncommon, so its likely that this isn’t an issue for the average consumer.
Let's discuss exactly what each clarity grade means. Diamonds in the flawless category are free from internal and external blemishes when examined by a skilled observer under 10X magnification (see below). Diamonds in the internally flawless category have no internal imperfections but some surface blemishes may be present.
The level of polish blemishes can be ascertained by reading the polish grade on Internally Flawless Clarity graded diamonds. Stones that have Flawless grade must grade Excellent for polish. Flawless graded diamonds are very uncommon, so its likely that this isn’t an issue for the average consumer.
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