Diamond clarity 1570741 225335392 2008-07-13T04:03:53Z 70.145.115.177 grammar, flow, spelling '''Diamond clarity''' is a quality of [[Diamond (gemstone)|diamond]]s relating to the existence and visual appearance of internal characteristics of a diamond called ''inclusions'', and surface defects called ''blemishes''. Clarity is one of the '''four Cs''' of diamond grading, the others being [[carat (mass)|carat]], [[diamond color|color]], and [[diamond cut|cut]]. Inclusions may be crystals of a foreign material or another diamond crystal, or structural imperfections such as tiny cracks that can appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of a diamond. A clarity grade is assigned based on the overall appearance of the stone under 10x magnification. Most inclusions present in gem-quality diamonds do not affect the diamonds' performance or structural integrity. However, large clouds can affect a diamond's ability to transmit and scatter light. Large cracks close to or breaking 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 [[fingerprint]]s. 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. ==Inclusions and blemishes== {{main|Diamond flaws}} There are several types of inclusions and blemishes, which affect a diamond's clarity to varying degrees. Features resulting from [[diamond enhancement]] procedures, such as ''laser lines'', are also considered inclusions and/or blemishes. ===Inclusions=== *Clouds *Feathers *Included crystals or minerals *Knots *Cavities *Cleavage *Bearding *Internal graining The diamond industry uses the term "internal characteristics" instead of "inclusions". For natural diamonds, the "internal characteristics" in the diamond are growth crystals that give the diamond its character and unique fingerprint. When diamonds are graded they are magnified at 10x power. ===Blemishes=== *Polish lines *Grain boundaries *Naturals *Scratches *Nicks *Pits *Chips ==Clarity grading== ===Gemological Institute of America (GIA)=== ====History==== In [[1952]], [[Richard T Liddicoat]], along with [[Lester Bensen]], [[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''.<ref name=GIAClarity/> In [[1953]], they released their new system which assessed three aspects of diamonds; ''make'', ''color'' and ''clarity''.<ref name=GIAClarity/> They took terminology used in the industry at the time and refined the definitions to produce a clarity scale by which diamonds could consistently be graded.<ref name=GIAClarity/> The system at that time contained nine grades, ''flawless'', ''VVS<sub>1</sub>'', ''VVS<sub>2</sub>'', ''VS<sub>1</sub>'', ''VS<sub>2</sub>'', ''SI<sub>1</sub>'', ''SI<sub>2</sub>'', ''I<sub>1</sub>'', and ''I<sub>2</sub>''.<ref name=GIAClarity/> The ''I'' of the ''I<sub>1</sub>'', and ''I<sub>2</sub>'' grades stood for ''imperfect''.<ref name=GIAClarity/> During the 1970s two changes were made to the system. Firstly, 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.<ref name=GIAClarity/> 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<sub>1</sub>.<ref name=GIAClarity/> The second change made to the grading system, was the introduction of the I<sub>3</sub> grade. This change was made in response to a growing number of diamonds of very low clarity being cut.<ref name=GIAClarity/> The last change to the clarity grading system took place in the 1990s when the term ''imperfect'' was updated to ''included''.<ref name=GIAClarity/> ====The GIA grading system today==== {| class="wikitable" align=center style="width: 90%; table-layout: fixed; text-align: center" |+GIA diamond clarity grading scale | style="border-right: 2px solid black" | '''Category''' | style="border-right: 2px solid black" | Flawless | style="border-right: 2px solid black" | Internally Flawless | colspan="2" style="border-right: 2px solid black" | Very Very Slightly Included | colspan="2" style="border-right: 2px solid black" | Very Slightly Included | colspan="2" style="border-right: 2px solid black" | Slightly Included | colspan="3" style="border-right: 2px solid black" | Included |- | style="border-right: 2px solid black" | '''Grade''' | style="border-right: 2px solid black" | '''FL''' | style="border-right: 2px solid black" | '''IF''' | '''VVS<sub>1</sub>''' | style="border-right: 2px solid black" | '''VVS<sub>2</sub>''' | '''VS<sub>1</sub>''' | style="border-right: 2px solid black" | '''VS<sub>2</sub>''' | '''SI<sub>1</sub>''' | style="border-right: 2px solid black" | '''SI<sub>2</sub>''' | '''I<sub>1</sub>''' | '''I<sub>2</sub>''' | style="border-right: 2px solid black" | '''I<sub>3</sub>''' |} The GIA diamond grading scale is divided into six categories and eleven grades.<ref name=GIAClarity>"Diamonds and Diamond Grading" course material - Book 11, Grading Clarity, Gemological Institute of America, 2002</ref> The clarity categories and grades are: *Flawless category (FL) diamonds have no inclusions or blemishes visible under 10x magnification.<ref name=GIAclarityonline>[http://www.gia.edu/library/4286/6278/faq_detail_page.cfm What is the GIA Clarity Scale for diamonds?] GIA website, accessed December 7 2006</ref> *Internally Flawless category (IF) diamonds have no inclusions visible under 10x magnification, only small blemishes on the diamond surface<ref name=GIAclarityonline/> *Very, Very Slightly Included category (VVS) diamonds have minute inclusions that are difficult for a skilled grader to see under 10x magnification.<ref name=GIAclarityonline/> The VVS category is divided into two grades; VVS1 denotes a higher clarity grade than VVS2. Pinpoints and needles set the grade at VVS<ref name=GIAClarity/> *Very Slightly Included category (VS) diamonds have minor inclusions that are difficult to somewhat easy for a trained grader to see when viewed under 10x magnification.<ref name=GIAclarityonline/> The VS category is divided into two grades; VS1 denotes a higher clarity grade than VS2. Typically the inclusions in VS diamonds are invisible without magnification, however infrequently some VS2 inclusions may still be visible to the eye. An example would be on a large emerald cut diamond which has a small inclusion under the corner of the table. <ref name=GIAClarity/> *Slightly Included category (SI) diamonds have noticeable inclusions that are easy to very easy for a trained grader to see when viewed under 10x magnification.<ref name=GIAclarityonline/> The SI category is divided into two grades; SI1 denotes a higher clarity grade than SI2. These may or may not be noticeable to the naked eye.<ref name="Pagel"/> *Included category (I) diamonds have obvious inclusions that are clearly visible to a trained grader under 10x magnification.<ref name=GIAclarityonline/> Included diamonds have inclusions that are usually visible without magnification or have inclusions that threaten the durability of the stone. The I category is divided into three grades; I1 denotes a higher clarity grade than I2, which in turn is higher than I3. Inclusions in I1 diamonds often are seen to the unaided eye. I2 inclusions are easily seen, while I3 diamonds have large and extremely easy to see inclusions that typically impact the brilliance of the diamond, as well as having inclusions that are often likely to threaten the structure of the diamond. <ref name=GIAClarity/> =====GIA clarity grading procedure===== GIA clarity grading is performed under 10x magnification with darkfield illumination. The GIA Gem Trade 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 light filtered overhead light. When grading is performed using a 10x handheld loupe, 'darkfield' illumination is more difficult to achieve. The grader must use 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 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 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 10x magnification to make an assessment of its impact on the clarity grade.<ref name ="GIAManual"/> If a stereo binocular microscope has been used, a final assessment using a 10x loupe is performed before the final judgment is made on the clarity of the stone. The grader first decides the clarity category of the diamond using one of the keywords ''none'' (FL, or IF if blemished), ''minute'' (VVS), ''minor'' (VS), ''noticeable'' (SI), or ''obvious'' (I). The decision is then made on the grade of the diamond.<ref name ="GIAManual">''Diamond Grading: Lab Manual'' Gemological Institute of America, Carlsbad, 2004</ref> ===Grading systems by other organizations=== The clarity grading system developed by the GIA has been used throughout the industry as well as by other diamond grading agencies including the [[American Gemological Society]] (AGS), [[European Gemological Laboratory]] (EGL), and the [[International Gemological Laboratory]] (IGL). 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 10x [[magnification]]. ====Confédération Internationale de la Bijouterie, Joaillerie, Orfèvrerie des Diamants, Perles et Pierres (CIBJO)==== {| class="wikitable" align=center style="width: 90%; table-layout: fixed; text-align: center" |+CIBJO diamond clarity grading scale | colspan="4" style="border-right: 2px solid black" | '''GIA''' | colspan="4" style="border-right: 2px solid black" | '''all stones''' | colspan="2" style="border-right: 2px solid black" | FL | colspan="2" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="5" | SI<sub>1</sub> | colspan="5" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="4" | I<sub>1</sub> | colspan="4" | I<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | I<sub>3</sub> |- | colspan="4" style="border-right: 2px solid black" | '''CIBJO''' | colspan="4" style="border-right: 2px solid black" | '''over 0.47ct'''<ref name="Pagel">Pagel-Thielsen, Verena G.G., F.G.A. ''Diamond Grading ABC: The Manual'' Rubin & Son n.v., Antwerp, 9th edition, 2001, ISBN 3-9800434-6-0. </ref> | colspan="4" style="border-right: 2px solid black" | Loupe clean | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="5" | SI<sub>1</sub> | colspan="5" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="4" | P<sub>I</sub> | colspan="4" | P<sub>II</sub> | colspan="4" style="border-right: 2px solid black" | P<sub>III</sub> |- | colspan="4" style="border-right: 2px solid black" | '''CIBJO''' | colspan="4" style="border-right: 2px solid black" | '''under 0.47ct''' | colspan="4" style="border-right: 2px solid black" | Loupe clean | colspan="6" style="border-right: 2px solid black" | VVS | colspan="6" style="border-right: 2px solid black" | VS | colspan="10" style="border-right: 2px solid black" | SI | colspan="4" | P<sub>I</sub> | colspan="4" | P<sub>II</sub> | colspan="4" style="border-right: 2px solid black" | P<sub>III</sub> |} The [[CIBJO]] or the ''International Confederation of Jewellery, Silverware, Diamonds and Stones'' developed the ''International Clarity Scale'' for grading diamonds. This clarity scale mirrors the GIA grading scale, except nomenclature varies. The CIBJO 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), Pique (P1, P2, and P3). Clarity grading by CIBJO standards is by examination using a 10x [[achromatic lens|achromatic]], [[aplanatic]] loupe in normal light.<ref name="Pagel"/> ====American Gem Society==== {| class="wikitable" align=center style="width: 100%; table-layout: fixed; text-align: center" |+AGS diamond clarity grading scale | colspan="2" style="border-right: 2px solid black" | '''GIA''' | colspan="2" style="border-right: 2px solid black" | FL | colspan="2" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="3" | SI<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="4" | I<sub>1</sub> | colspan="4" | I<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | I<sub>3</sub> |- | colspan="2" style="border-right: 2px solid black" | '''AGS''' | colspan="4" | 0 | colspan="3" | 1 | colspan="3" | 2 | colspan="3" | 3 | colspan="3" | 4 | colspan="3" | 5 | colspan="3" | 6 | colspan="3" | 7 | colspan="3" | 8 | colspan="3" | 9 | colspan="3" | 10 |} The American Gem Society grades clarity on 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.<ref name="TheAGSWay"/> Clarity grading by AGS standards requires examination using a binocular stereo microscope equipped with adjustable zoom magnification and darkfield illumination. <ref name="TheAGSWay">''The AGS Way: Diamond Grading Standards'' American Gem Society, 1999</ref> ====International Diamond Council (IDC)==== {| class="wikitable" align=center style="width: 90%; table-layout: fixed; text-align: center" |+IDC diamond clarity grading scale | colspan="4" style="border-right: 2px solid black" | '''GIA''' | colspan="2" style="border-right: 2px solid black" | FL | colspan="2" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border- | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="5" | SI<sub>1</sub> | colspan="5" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="4" | I<sub>1</sub> | colspan="4" | I<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | I<sub>3</sub> |- | colspan="4" style="border-right: 2px solid black" | '''IDC''' | colspan="4" style="border-right: 2px solid black" | Loupe clean | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="5" | SI<sub>1</sub> | colspan="5" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="4" | P<sub>I</sub> | colspan="4" | P<sub>II</sub> | colspan="4" style="border-right: 2px solid black" | P<sub>III</sub> |} 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 10x achromatic, aplanatic loupe in normal light.<ref name="Pagel"/> ====European Gemological Laboratory==== {| class="wikitable" align=center style="width: 100%; table-layout: fixed; text-align: center" |+EGL diamond clarity grading scales | colspan="4" style="border-right: 2px solid black" | '''GIA''' | colspan="2" style="border-right: 2px solid black" | FL | colspan="2" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="5" | SI<sub>1</sub> | colspan="5" style="border-right: 2px solid black" | SI<sub>2</sub> | colspan="5" | I<sub>1</sub> | colspan="4" | I<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | I<sub>3</sub> |- | colspan="4" style="border-right: 2px solid black" | '''EGL USA''' <ref>[http://www.eglusa.com/clarity.html EGL USA clarity scale]</ref> | colspan="4" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="4" | SI<sub>1</sub> | colspan="4" | SI<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | SI<sub>3</sub> <ref>Tashey Thomas E. Jr, Roskin Gary A. [http://www.eglcanada.ca/media/Defining%20SI3.pdf European Gemological Laboratory Defines SI3] Cornerstone, Summer 1992 – A publication for Accredited Gemologist Association, accessed online February 18, 2007</ref> | colspan="3" | I<sub>1</sub> | colspan="4" | I<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | I<sub>3</sub> |- | colspan="4" style="border-right: 2px solid black" | '''EGL India''' <ref>[http://www.eglindia.biz/fourcs.htm EGL India clarity scale]</ref> | colspan="2" style="border-right: 2px solid black" | FL | colspan="2" style="border-right: 2px solid black" | IF | colspan="3" | VVS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VVS<sub>2</sub> | colspan="3" | VS<sub>1</sub> | colspan="3" style="border-right: 2px solid black" | VS<sub>2</sub> | colspan="4" | SI<sub>1</sub> | colspan="4" | SI<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | SI<sub>3</sub> | colspan="3" | P<sub>1</sub> | colspan="4" | P<sub>2</sub> | colspan="4" style="border-right: 2px solid black" | P<sub>3</sub> |} The [[European Gemological Laboratory]] (EGL) introduced 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 "eye clean", that is, which have inclusions which are not obviously visible to the naked eye. ==Clarity grading considerations== All grades reflect the appearance to an experienced grader when viewed from above at 10x 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, otherwise called: ''grade setting inclusions''. This means that less significant inclusions are ignored for the purposes of setting the grade. However, they may still be plotted onto a diamond plot chart.<ref name=GIAClarity/> Accurate clarity grading as with other grading steps must be done with the diamond ''loose''; meaning not set into any mounting. Inclusions are often difficult to see from the ''crown'' side of the diamond, and may be concealed by the setting. ===Size=== 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.<ref name=GIAClarity/> ===Number=== 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 the actual number of characteristics. <ref name=GIAClarity/> ===Position=== 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 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.<ref name=GIAClarity/> In addition the position of large ''feathers'', ''knots'' and ''included crystals'' positioned where they extend to the girdle or crown of the stone, affect the clarity grade. Diamonds worn in jewelry typically will withstand breakage, however inclusions of this ''nature'', 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.<ref name=GIAClarity/> ===Nature=== The fourth clarity factor which is assessed is a characteristic's ''nature''. The characteristic's nature determines whether it is ''internal'' where they extend into the stone, or ''external;'' where they are 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.<ref name=GIAClarity/> A diamond's internal characteristics can be a; ''bruise'', ''cavity'', ''chip'', ''cleavage'', ''cloud'', ''crystal'', ''feather'', ''grain center'', ''indented natural'', ''internal graining'', ''knot'', ''laser drill hole'', ''needle'', ''pinpoint'', or ''twinning wisp''.<ref name=GIAClarity/> A diamond's external characteristics can be an; ''abrasion'', ''natural'', ''nick'', ''pit'', ''polish lines'', ''polish mark'', ''scratch'', ''surface graining'', or ''extra facet''.<ref name=GIAClarity/> The ''nature'' will also detail whether an inclusion poses a risk to the stone. Inclusions that cause or may cause a break in the crystal structure (included crystal, feather, knot, cleavage) are considered alongside their ''position'', to assess whether they pose a moderate level of risk for further breakage.<ref name=GIAClarity/> ===Color or relief=== 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 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''.<ref name=GIAClarity/> == Rarity and value == Diamonds become increasingly rare when considering higher clarity gradings {{Fact|date=February 2007}}. Only about 20 percent of all diamonds mined have a clarity rating high enough for the diamond to be considered appropriate for use as a gemstone; the other 80 percent are relegated to industrial use. Of that top 20 percent, 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 are known as "eye-clean" and are preferred by most buyers {{Fact|date=February 2007}}, although visible inclusions can sometimes be hidden under the setting in 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 {{Fact|date=February 2007}}, while I stones are shunned by most buyers {{Fact|date=February 2007}}. FL and IF stones are sometimes referred to as "museum quality" or "investment grade" to denote their rarity {{Fact|date=February 2007}}, although the term "investment grade" is misleading as diamonds have historically been [[liquidity|illiquid]] and questionable stores of value. == Clarity enhancement == {{main|Diamond enhancement}} Laser "drilling" involves using 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. GIA, as a matter of policy, does NOT certify clarity-enhanced diamonds. If you see a GIA Diamond Report with the words "clarity enhanced" or "fracture-filled," it is surely a counterfeit report. 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 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 isn't 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 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. ==See also== * [[Diamond]] * [[Diamond enhancement]] * [[Synthetic diamond]] ==References== <references/> [[Category:Diamond]] [[hu:Gyémántok tisztasága]]