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41-400: Inclusions are solids, liquids, or gases that were trapped in a mineral as it formed. They may be crystals of a foreign material or even another diamond crystal, or may have produced structural imperfections, such as tiny cracks that make a diamond appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of

82-509: A binocular stereo microscope equipped with adjustable zoom magnification and darkfield illumination. The IDC or the International Diamond Council uses a very similar standard to CIBJO. IDC loupe clean stones that have external blemishes have notations made on the grading report. IDC clarity grading is by examination using a 10× achromatic, aplanatic loupe in normal light. The European Gemological Laboratory (EGL) introduced

123-405: A characteristic lies within the stone, on the stones surface, or both. If the grader is using a stereo microscope, they may zoom in to a higher magnification to make closer observations of an inclusion, but then return to 10× magnification to make an assessment of its impact on the clarity grade. If a stereo binocular microscope has been used, a final assessment using a 10× loupe is performed before

164-433: A diamond may be classified as a(n): bruise, cavity, chip, cleavage, cloud, crystal, feather, grain center, indented natural, internal graining, knot, laser drill hole, needle, pinpoint, or twinning wisp. An external characteristic of a diamond may be classified as a(n): abrasion, natural, nick, pit, polish lines, polish mark, scratch, surface graining, or extra facet. The nature will also determine whether an inclusion poses

205-533: A diamond's clarity to varying degrees. Features resulting from diamond enhancement procedures, such as laser lines, are also considered inclusions or blemishes. In 1952, Richard T. Liddicoat , along with Marquis Person , Joe Phillips, Robert Crowningshield and Bert Krashes began to work on a new diamond grading system which they called the "diamond grading and evaluation appraisal". In 1953, they released their new system which assessed three aspects of diamonds; make, color and clarity. They took terminology used in

246-457: A diamond. A clarity grade is assigned based on the overall appearance of the stone under ten times magnification, which is the standard magnification for loupes used in the gem world. Most inclusions present in gem-quality diamonds do not affect the diamonds' performance or structural integrity and are not visible to the naked eyes. However, large clouds can affect a diamond's ability to transmit and scatter light. Large cracks close to or breaking

287-439: A flash of color, commonly orange or pink, when viewed closely. There is a significant price discount for fracture-filled diamonds. The GIA will not grade fracture-filled diamonds, in part because the treatment is not as permanent as the diamond itself. Reputable companies often provide for repeat treatments if heat causes damage to the filling. The heat required to cause damage is that of a blowtorch used to work on settings, and it

328-399: A gemstone; the other 80% are relegated to industrial use. Of that top 20%, a significant portion contains an inclusion or inclusions that are visible to the naked eye upon close inspection. Those that do not have a visible inclusion when the gem is examined approximately 6 inches from the naked eye are known as "eye-clean", although visible inclusions can sometimes be hidden under the setting in

369-470: A laser to burn a hole to a colored inclusion, followed by acid washing to remove the coloring agent. The clarity grade is the grade after the treatment. The treatment is considered permanent. Clarity can also be "enhanced" by filling the fracture much like a car windshield crack can be treated. Such diamonds are sometimes called " fracture filled diamonds". Reputable vendors must disclose this filling and reputable filling companies use filling agents which show

410-409: A light source in such a way that the base of the stone is lit from the side, and the crown of the stone is shielded from the light. After thoroughly cleaning the diamond, the diamond is picked up using tweezers in a girdle-to-girdle hold. The grader views the diamond for the first time through the table, studying the culet area of the stone for inclusions. The diamond is then set down and picked up with

451-517: A new breed of "certified" jewelers. These jewelers would form the foundation of the Gemological Institute of America (GIA), and later the AGS. In its history, the AGS has achieved significant accomplishments within the field of gemology and jewelry. Among these are the following: A big part of the AGS operation comes in the form of AGS Laboratories, which offers laboratory services to members of

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492-546: A number scale between 0 and 10. These numbers grades correlate almost exactly with the GIA system, but with some differences. The flawless and internally flawless (0) grades are grouped together with notation defining whether the stone is free from external blemishes, the VVS through SI grades are numbered 1 through 6, and then there are four grades 7 through 10 for the included category. Clarity grading by AGS standards requires examination using

533-468: A piece of jewelry. The most expensive gem diamonds fall within the VS and SI grades with FL, IF, and even VVS stones commanding significant premiums. FL and IF stones are sometimes referred to as "museum quality" or "investment grade" to denote their rarity although the term "investment grade" is misleading as diamonds have historically been illiquid and questionable stores of value. Laser "drilling" involves using

574-438: A risk to the stone. An inclusion that may cause a break in the crystal structure (included crystal, feather, knot, and cleavage) may, depending on its position, pose a moderate level of risk for further breakage. The fifth clarity factor which is assessed is the color and relief of clarity characteristics. Characteristics that contrast with the surrounding diamond are said to have "relief". The degree to which this color and relief

615-404: Is an important tool in the study of climate change . A xenolith is a preexisting rock which has been picked up by a lava flow. Melt inclusions form when bits of melt become trapped inside crystals as they form in the melt. Inclusions are one of the most important factors when it comes to gem valuation. They diminish the clarity and value of many gemstones, such as diamonds , and increase

656-456: Is assessed is a characteristic's nature. The characteristic's nature determines whether it is internal (extending into the stone) or external (limited to the surface of the stone). Internal characteristics automatically exclude the diamond from the Flawless , and Internally Flawless categories. External characteristics exclude the diamond from the Flawless category. An internal characteristic of

697-714: Is based in Las Vegas, Nevada , along with the affiliated American Gem Society Laboratories (AGSL) (founded in 1996) and the American Gem Society Advanced Instruments Division (founded in 2004). The Society trains and certifies jewelers , gemologists, and jewelry appraisers . Diamond grading is a specialty of the American Gem Society Laboratories and the Society has developed its own cut , color , and clarity standards. The AGS

738-423: Is essential to inform anyone working on a setting if the diamond is fracture-filled, so they can apply cooling agents to the diamond and use greater care while working on it. GIA, as a matter of policy, does not grade clarity-enhanced diamonds but it will grade laser-drilled diamonds since it considers the enhancement to be permanent in nature. If a GIA report has the words "clarity enhanced" or "fracture filled", it

779-414: Is noticeable affects the clarity grade of the diamond. Colored inclusions invariably show contrast and are more easily seen. An exception is a black pinpoint inclusion, which is often more difficult to see than a white pinpoint. Diamonds become increasingly rare as clarity increases. Only about 20% of all diamonds mined have a clarity rating high enough for the diamond to be considered appropriate for use as

820-427: Is performed under 10× magnification with darkfield illumination. The GIA Laboratory uses as standard equipment binocular stereo microscopes which are able to zoom to higher magnifications. These microscopes are equipped with darkfield illumination, as well as an ultraviolet filtered overhead light. When grading is performed using a 10× handheld loupe, darkfield illumination is more difficult to achieve. The grader must use

861-646: Is surely a counterfeit report. Inclusion (mineral) In mineralogy , an inclusion is any material trapped inside a mineral during its formation. In gemology , it is an object enclosed within a gemstone or reaching its surface from the interior. According to James Hutton 's law of inclusions, fragments included in a host rock are older than the host rock itself. Inclusions are usually rocks or other minerals, less often water, gas or petroleum . Liquid and vapor create fluid inclusions . In amber , insects and plants are common inclusions. The analysis of atmospheric gas bubbles as inclusions in ice cores

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902-688: The American Gemological Society (AGS), and the International Gemological Institute (IGI). There are other smaller labs which use the GIA system as well. These grading agencies base their clarity grades on the characteristics of inclusions visible to a trained professional when a diamond is viewed from above under 10× magnification . The World Jewellery Confederation developed the International Clarity Scale for grading diamonds. This clarity scale mirrors

943-468: The Internally Flawless grade was added, as GIA noticed that many diamonds were being aggressively cut to remove any surface blemishes, and thereby reducing the cutting quality ("make") of the diamonds. The Internally Flawless grade gave diamond manufacturers a choice to leave blemishes on the surface of the stone, and achieve a grade higher than VVS 1 . The second change made to the grading system

984-441: The GIA grading scale, except nomenclature varies. The system names these clarity grades; Loupe Clean, Very, very small inclusions (VVS1 and VVS2), Very small inclusions (VS1 and VS2), Small inclusions (SI1 and SI2), Piqué (P1, P2, and P3; from a French word meaning "blemished"). Clarity grading by WJC standards is by examination using a 10× achromatic , aplanatic loupe in normal light. The American Gem Society grades clarity on

1025-450: The SI3 as a clarity grade. While intended as a range to include borderline SI2 / I1 stones, it is now commonly used to mean I1's which are nearly "eye clean", that is, which have inclusions which are not obviously visible to the naked eye. Because GIA and EGL use the same nomenclature, but apply the standards differently, purchasers of diamonds can be easily confused or mislead. All grades reflect

1066-449: The actual number of characteristics. The third clarity factor which is assessed is the characteristic's position. When an inclusion is directly under the table of the diamond it is most visible. An inclusion under the table and positioned close to a pavilion facet will reflect multiple times around the stone, giving this type of inclusion the name "reflector". Reflectors are graded as if each reflection were an inclusion (although in plotting

1107-425: The appearance to an experienced grader when viewed from above at 10× magnification, though higher magnifications and viewing from other angles are used during the grading process. The grader studies the diamond for internal characteristics and judges them on the basis of five clarity factors: size, number, position, nature, and color or relief. The clarity grade is assessed on the basis of the most noticeable inclusions,

1148-452: The diamond it is only plotted once). For this reason, reflectors have a greater impact on the clarity grade. Inclusions become less visible when they are positioned under the crown facets, or near the girdle of the stone. These inclusions may often be more easily seen from the pavilion side of the diamond than from crown side of the diamond. Additionally, the position of large feathers, knots and included crystals positioned where they extend to

1189-406: The final judgment is made on the clarity of the stone. The grader first decides the clarity category of the diamond: none (FL, or IF for a blemish), minute (VVS), minor (VS), noticeable (SI), or obvious (I). The decision is then made on the grade of the diamond. The clarity grading system developed by the GIA has been used throughout the industry as well as by other diamond grading agencies including

1230-467: The girdle or crown of the stone affect the clarity grade. Diamonds worn in jewelry typically will withstand breakage, however inclusions of this nature and in these positions can pose a risk for further extension of the break in the structure of the diamond. Inclusions that are judged to pose at least a moderate risk of breakage to the stone are graded in the Included category. The fourth clarity factor which

1271-401: The industry at the time and refined the definitions to produce a clarity scale by which diamonds could be consistently graded. The system at that time contained nine grades: Flawless, VVS 1 , VVS 2 , VS 1 , VS 2 , SI 1 , SI 2 , I 1 , and I 2 . The 'I' of the I 1 , and I 2 grades originally stood for "Imperfect". During the 1970s, two changes were made to the system. Firstly,

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1312-491: The jewelry industry. Primary among these are their diamond grading services. Jewelers are able to have their diamonds scientifically evaluated according to the Four Cs: Color, Clarity, Cut, and Carat Weight. They are then given a diamond grading report, which can be provided to a consumer in order to verify the quality of the diamond they are purchasing. Additionally, AGS Laboratories offers laser inscription services. Through

1353-416: The melt solidifies. The term is usually used negatively such as when the particle could act as a fatigue crack nucleator or as an area of high stress intensity. American Gemological Society The American Gem Society ( AGS ) is a trade association of retail jewelers, independent appraisers , suppliers, and selective industry members, which was founded in 1934 by Robert M. Shipley. The Society

1394-499: The profession at the time. Shipley lost his jewelry stores in a divorce and went to Europe, where he completed the Great Britain National Association of Goldsmiths gemological correspondence course. He brought his newfound expertise back to Los Angeles, where he founded his own preliminary course in gemology on September 16, 1930. For the next few years he worked to promote the need for gemological education and train

1435-449: The setting. The first clarity factor which is assessed is a clarity characteristic's size. Larger characteristics are typically more noticeable under magnification, thereby placing the diamond into a lower clarity grade. The second clarity factor which is assessed is the number of clarity characteristics. Generally, the more characteristics, the lower the clarity grade. This assessment is made by judging how readily they can be seen, not by

1476-406: The so-called "grade setting inclusions". Less significant inclusions are ignored for the purposes of setting the grade; however, they may still be plotted onto a diamond plot chart. Accurate clarity grading as with other grading steps must be done with the diamond "loose", i.e. not set into any mounting. Inclusions are often difficult to see from the crown side of the diamond, and may be concealed by

1517-725: The surface may reduce a diamond's resistance to fracture. Diamonds with higher clarity grades are more valued, with the exceedingly rare "Flawless" graded diamond fetching the highest price. Minor inclusions or blemishes are useful, as they can be used as unique identifying marks analogous to fingerprints . In addition, as synthetic diamond technology improves and distinguishing between natural and synthetic diamonds becomes more difficult, inclusions or blemishes can be used as proof of natural origin. Heavily included diamonds used to be solely for industrial use. In recent years, salt and pepper diamonds have gained increasing popularity. There are several types of inclusions and blemishes, which affect

1558-468: The tweezers in a table-to-culet hold. In this position, the diamond can be studied from the pavilion side, and the crown side, examining the diamond through each facet for inclusions. Once a sector of the diamond has been thoroughly examined, the grader rotates the diamond in the tweezer, so that the neighboring sector can be examined. The grader uses darkfield lighting to reveal characteristics, and alternates to reflected, overhead lighting to ascertain whether

1599-411: The value of others, such as star sapphires . Many colored gemstones are expected to have inclusions which do not greatly affect their values. They are categorized into three types: The term "inclusion" is also used in the context of metallurgy and metals processing. During the melt stage of processing particles such as oxides can enter or form in the liquid metal which are subsequently trapped when

1640-415: Was created by Robert M. Shipley. During the 1920s, Shipley was operating quite successfully as a jeweler. However, despite his years in the industry, his lack of expertise regarding gems and jewelry was revealed to him by a pair of his best customers. Humbled by this revelation, Shipley realized that this was a big problem among American jewelers, one which likely accounted for much of the public's distrust for

1681-405: Was the introduction of the I 3 grade. This change was made in response to a growing number of diamonds of very low clarity being cut. The last change to the clarity grading system took place in the 1990s when the term "imperfect" was changed to "included". The GIA diamond grading scale is divided into six categories and eleven grades. The clarity categories and grades are: GIA clarity grading

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