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Clarity in Diamonds - Gemstones & Clouds

This figure to fix the clarity grading system used by the diamond trade both here and in Europe. GIA and EGL and HRD use the same nominal culture for grading clarity other there maybe differences in how they great. The HRD for instance tends to rely more heavily on quantitative measurements specifying how many microns of flocking the end in size in order to qualify a diamond for a certain clarity category. But generally speaking the clarity grains are defined as follows: flawless, this is of course the ultimate clarity grade. The description means that under 10 power mice magnification are there with the microscope or jewelers loop neither internal or external flaws can be seen. That is their neither surface scratches or blemishes or inclusions within the body of the diamonds. The definition does not permit an extra facet on the pavilion which is the bottom of the stone so long as it cannot be seen when the stone is looking straight down on the table. Also permitted as a minor natural which is a remaining bit of the original rough stone surface on the edge of the girdle. The girls the circumference around the base of the crown which divides the top of the diamond from the bottom. Finally growth for twin lines along the crystal structure are allowed so long as they do not reach the outer surface and so long as they do not distort the color or the pastor light. It should be noted that the GIA and EGL almost never issue a flawless certificate. Inevitably there will be a microscopic finishing damage on the Xterra of the diamond during the cutting process. The blemish disqualifies the diamond for the flawless designation. For all intents and purposes in an internally flawless is the top clarity grade. Furthermore there is almost no price difference between a flawless and internally flawless diamond.

Just as the name signifies an internally flawless stone must meet the internal criteria as the first category flawless but the surface of the Cutstone is more flawed. It may have too many extra facets finish blemishes cutting marks are too many obvious naturals and so forth. DVS one and DDS to are two creations of the very very small inclusions category the first grade below flawless. Stones in this category I have tiny fuzz that evening expert using attended how her medication has great difficulty detecting. DVS is subdivided into BDS one and TVS to the former being the higher grade the latter the lower. A previous one has even more many and hard-to-find inclusions then does a devious too. The location of the internal flaws is also an important determinant of which previous creative stone is given. If the inclusions are the periphery of the stone away from the central area under the table that is usually called a VPS one assuming the flaws are small enough. If the flaws are still menu but are located more sensually and therefore more in the way of life fraction in the stone is apt to be given the slightly lower grade of CVS too. Further surface scratches and blemishes must be very minor.

VS one and VS two these our stones with very small inclusions defined as flaws that are still difficult for the gym on just to locate under the 10 power magnification but less so than the previous great. Finish imperfections may also be a bit more significant but still relatively minor. SI one and SI to our stones with small inclusions. With the naked eye but are big enough to checks substantially from the passage of life and hence the brilliance of the diamond. Sometimes the grade is also called slightly imperfect. In fact some people substitute him perfect for inclusion rather clarity scale. But imperfection as opposed to inclusion is a tricky term. Even a flawless diamond under the widely accepted definition given above is not perfect or faultless in the true sense.

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Gemologists & Color Grading

The internationally accepted measurement for clarity must be done under of 10 power magnification. If no flaws can be seen at that degree of magnification the diamond is deemed to be flawless the highest possible clarity grade diamond and obtained. It is important that the stone not be mounted when inspected as the setting can hide imperfections but before arriving at that determination a laboratory gym I was just will usually turn his microscopes up to 40 power or even hired to view the diamonds flaws. After locating any inclusions that there may be he then reduces the magnification back down to 10. Is at that power the flaws can no longer be seen in the stone is judged to be flawless. Some flaws can still be seen in the power and the grading is reduced. Therefore international yardstick for judging clarity is 10 power magnification. No more no less.

Incidentally it takes an experience geologist to do this. An average person might see tricks of the brain and optic nerves attend to afflict to The untrained eye. Anything seen at a 40 power or higher tends to imprint itself in the mind so that I can still be seen even when the microscope is returned to the lower degree of magnification. By the same token when you see with your naked eye is meaningless. The stone may look flawless and you're contend the flaws to reduce its value by tens of thousands of dollars.

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The Difference in Color Grading Scales

Color grades are considered best for investment RD through H on the GIA scale corresponds to 032 on the EGL scale. You should always insist on a certificate from a recognized in reputable gemological laboratory that attest to one of these colored greats. However if you wish to personally examine diamonds you're considering buying you should be aware of the conditions that are considered by the trade ideal for grading color. The traditional method of judging true color was by viewing the stone under natural north sunlight however sunlight isn't always dependable. Most laboratories nowadays use this eliminates the effect of ultraviolet florescence. Some fluorescents in the stone is not bad and doesn't necessarily detract from the stones value so long as it is pervasive in a stone and not concentrated in a single area. Fluorescents may even enhance a diamonds fire or brilliance but it shouldn't interfere with your judgment or the gemological judgment of the Stone's true color.

A stone is usually color graded by viewing the stone unmounted from the top that is by looking straight down on its table the broad flat facet on the top of the round brilliant cut diamonds. The background should be white. And above all regardless of the lighting employed the diamond should be compared side-by-side against a set of master stones. Austin gym I'll just use a phosphorous specter scope to analyze color more scientifically by measuring exactly as stones nitrogen content. The Lehman should never deceive himself about being able to judge for himself the true color of the stone. Anyone who thinks he can attend his just kidding himself. And the steaks are very high. The dollar difference between a DN and H one carat flawless stone is around $50,000. Chicken lighting techniques can easily fool and on practice either. The bottom line is still a dependence on the reputation of the person who is selling you the diamond and of the greeting certificate to accompany it.

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International Standards for Diamond Color

An exception to board scale used by the highly respected HRD the Belgian base laboratory of the Belgian Hyatt diamond County this scale was approved in May 1978 nineteen seventy-eight by the Congress of world Federation of diamond marketplaces in the international diamond manufactures association. Luckily as far as combining in combating confusion's concerns that HRT's were descriptions of color exceptional white plus sectional white bread white and so forth correspond closely to the letter and number grades of the GIA and the EGL as can be seen in the chart. Not until you get to the color grade below H42 is their variation. IMJ are combined in a category called slightly tinted white by HRT. The next two color grades are also united as you can see. 

But this presents little problem for the investor who is mainly concerned with great HN above anyway. Colored grades range from colorless down to hockey tents of yellow which come from nitrogen and other impurities buffets in those two extremes the gradations are almost and perceptive. To the untrained eye of the Lehman a stone may appear colorless all the way down to the grade of J which is considered to be the bottom range of grades also considered cold near colorless. That grade may be fine as far as appearance is concerned for engagement rings or other jewelry purposes but an investor must be more discerning. 

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Comparing Two Diamonds on Cost

Finally take two stones in the same weight but in different grades. We in this example has little them with the exception of the fancy diamonds the pink blues canary yellow's and so forth when we speak of color in diamond, we are really speaking ideally have a lack of color. In recent years as laboratory techniques and equipment improved screening of color has been increasingly refined.

Traditionally color was graded in broad categories. For instance, the old Scandinavian systems top grade was River equivalent to that old British blue white category. Today under color grading standards developed first by the gemological Institute of America that category is broken down into three smaller upgrades DE and F.

The most important for The American investor are those of the GIA and the EGL that European gemological laboratory. Interestingly the EGL has taken to printing on its greeting certificates not only it's own number. But also the equivalent GIA letter grade. because these systems or detailed and exact an investor would be well advised to adhere and seek them out rather than risk the much figure and often abused vertical descriptions. If someone offers you a blue Whitestone for example run don't walk away from the deal.

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Diamond Measurements & Value

Points of stones between .9 5.99 very substantially between cutters and at the marketplace. Supply and demand is the most important determining factor. A stone of.99 99 nine five. And a.99 diamonds will sell for 10 to 20% less than a stone of the same quality way exactly one carat.

But carat weight is still only a relative importance. The internal and external characteristics of the diamond Color the degree of whiteness or color looseness clarity the degree of lawlessness cut the degree to which the time and conforms to excepted proportion standards make all the difference. Two similar looking 1 carat diamond have exactly the same way he can vary buy as much because $40,000 dollars per carat by virtue of slightly different quality features. For any given size the other three main factors break down this way. Color is by far the most important determinant making up about 50% of the average stones value. Clarity and cut are about equally important making up 25% each of the remaining value. This 50 2525 breakdown might seem to leave no room for the weight factor. In fact wait is of great importance but only in comparing stones in the context of their other qualities. The best way to illustrate this is by example. Let's say you're trying to choose between a 1 carat stone and 2 carat stone and they both have the same price tag. On the other hand one might expect 2 ^ flawless white diamond to be double the value of a one carat diamond of comparable quality but in fact the value would be more than doubled. This is because the larger stones of any grade are rarer.