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How GIA Grades Your Diamond
                                         Independent and nonprofit, GIA is considered the final word on

Tre a s u re o f Ti m e                  a diamond¡¯s authenticity and quality. GIA developed the 4Cs
                                         and the International Diamond Grading System?, the grading
                                                                                                                                                                                        Wonder of Nature
                                         standard adopted by jewelry professionals around the globe.
Every diamond is unique. Each reflects   GIA screens every gemstone to identify synthetics, simulants                                                                                   There is no other gemstone quite like a
the story of its arduous journey from    and known treatments. Expert gemologists ex amine each                                                                                         diamond. It is found in the most remote
                                         diamond under controlled lighting and viewing conditions, in
deep inside the earth to a cherished                                                                                                                                                    places on earth, and the fact that it
                                         order to provide the most rigorous assess-
object of adornment. Yet all diamonds    ments of a diamond¡¯s 4Cs.                                                                                                                      forms at all is something of a miracle. It
share cert ain features that allow us    Every G IA Diamond Grading Report or                                                                                                           takes about one ton of rock to recover
to compare and evaluate them. These      Diamond Dossier ? cont ains these assess-                                                                                                      less than half a carat of rough, making
                                         ments along with additional descriptive
features are called the 4Cs.                                                                                                                                                            diamond one of the rarest and most
                                         information and state-of-
                                         the-art security fea-                                                                           The World¡¯s Foremost Authority in Gemology ?   de sire d gem ston es in th e w orl d. A
                                         tures. Regarded as                                                                              The 4Cs of Diamond Qualit y                    diamond is a testament of endurance
                                         premier gemological
                                                                                                                                                                                        and strength ¨C and not surprisingly, the
                                         credentials by inter-
                                         national gem profes-                                                                                                                           ultimate symbol of love.
                                         sionals and fine jewelry
                                         houses, G IA Reports
                                         accompany the world¡¯s
                                         most legendary dia-
                                         monds ¨C and now, quite
                                         possibly, yours.

                                         To learn more about the 4Cs, GIA, its reports and services,
                                         visit www.gia.edu




                                         World Headquarters | The Robert Mouawad Campus
                                         5345 Armada Drive | Carlsbad, California 92008
                                         T: 800-421-7250 | T: 760-603-4000



                                                                                                                                The World¡¯s Foremost Authority in Gemology?
                                         COPYRIGHT ?2006 GEMOLOGICAL INSTITUTE OF AMERICA, INC. ALL RIGHTS RESERVED.   FC1106
GIA 4Cs



Color                                                              Clarity                                                 Cut                                                                             Carat Weight
          Th e G I A C o l o r S c a l e e x t e n d s f r o m D        The G IA Clarity Scale includes eleven                          Th e G I A C u t S c a l e r a n g e s f r o m E x c e l l e n t   One carat equals 200 milligrams in weight.
          (colorless) to Z (light yellow or brown).                     clarity grades ranging from Flawless to I 3.                    to Poor. G IA provides a cut quality grade for                     For diamonds under one carat, each carat is divided into
          Although many people think of gem quality                     Because diamonds form under tremendous                          standard round brilliant diamonds that fall in the GIA             100 points ¨C similar to pennies in a dollar. 0.75 ct. = 75
          diamonds as colorless, truly colorless diamonds               heat and pressure, it is extremely rare to find                 D-to-Z color range.                                                points, 1/2 ct. = 50 points.
          are actually very rare. Most diamonds used in                 a diamond that lacks any internal and external                  A polished diamond¡¯s beauty lies in its complex
          jewelry are nearly colorless with tints of yellow             characteristics. These characteristics are a by-                relationship with light: how light strikes the surface,
          or brown.                                                     product of its formation and help gemologists                   how much enters the diamond, and how, and in what
                                                                        separate natural diamonds from synthetics and                   form light returns to your eye.
                                                                        simulants, and identify individual stones.
                                                                                                                                        The result is a magnificent display of three attributes.
                                                                                                                                                                                                              0.50 ct.    0.75 ct.   1.00 ct.    2.00 ct.      5.00 ct.
                                                                                                                                        Brightness is the combination of all white light
                                                                                                                                        reflecting from the surface and interior of a diamond.
               D             H              N             Z                                                                             Fire describes the ¡°flares¡± of color emitted from
                                                                                                                                        a diamond. Scintillation describes the flashes of
          Color grades are determined by comparing                                                                                      light you see when the diamond, the light, or the
          each diamond to a master set. Each letter grade                                                                               observer moves.
          represents a range of color and is a measure of
                                                                                 VVS 2                             VS 2
                                                                                                                           A polished diamond¡¯s proportions affect its light performance,                  Beauty and Its Beholder                   The 4Cs provide a way
          how noticeable a color is.                                                                                       which in turn affects its beauty and overall appeal. Diamonds with              to objectively compare and evaluate diamonds, but numbers
                                                                                                                           fine proportions, symmetry, and polish optimize their interaction               alone can¡¯t describe a diamond¡¯s mysterious
                                                                                                                           with light, and have increased brightness, fire, and scintillation.             and captivating beauty ¨C for that, you¡¯ll
          Fluorescence Some diamonds can emit a visible                                                                                                                                                    have to visit your local jeweler to see
                                                                                                                                                star length       table size
          light when exposed to ultraviolet radiation, but                                                                                                                                                 one for yourself.
                                                                                                                                                                                                crown
          fluorescence is not a factor in determining color                                                                           girdle                                                    angle

          or clarity grades. However, a description of its
                                                                                  SI 2                              I2              thickness                                 crown height


          strength and color is provided on GIA Reports
                                                                                         Sample Clarity Diagrams                                                       total depth              pavilion
          as an additional identifying characteristic.                                                                                                                                          angle
                                                                                                                                                                               pavilion depth


                                                                                                                                                    lower
                                                                                                                                                 girdle/half
                                                                                                                                                facet length
                                                                                                                                                               culet

                                                                                                                                                        Anatomy of a Diamond

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Lab 4cs Brochure

  • 1. How GIA Grades Your Diamond Independent and nonprofit, GIA is considered the final word on Tre a s u re o f Ti m e a diamond¡¯s authenticity and quality. GIA developed the 4Cs and the International Diamond Grading System?, the grading Wonder of Nature standard adopted by jewelry professionals around the globe. Every diamond is unique. Each reflects GIA screens every gemstone to identify synthetics, simulants There is no other gemstone quite like a the story of its arduous journey from and known treatments. Expert gemologists ex amine each diamond. It is found in the most remote diamond under controlled lighting and viewing conditions, in deep inside the earth to a cherished places on earth, and the fact that it order to provide the most rigorous assess- object of adornment. Yet all diamonds ments of a diamond¡¯s 4Cs. forms at all is something of a miracle. It share cert ain features that allow us Every G IA Diamond Grading Report or takes about one ton of rock to recover to compare and evaluate them. These Diamond Dossier ? cont ains these assess- less than half a carat of rough, making ments along with additional descriptive features are called the 4Cs. diamond one of the rarest and most information and state-of- the-art security fea- The World¡¯s Foremost Authority in Gemology ? de sire d gem ston es in th e w orl d. A tures. Regarded as The 4Cs of Diamond Qualit y diamond is a testament of endurance premier gemological and strength ¨C and not surprisingly, the credentials by inter- national gem profes- ultimate symbol of love. sionals and fine jewelry houses, G IA Reports accompany the world¡¯s most legendary dia- monds ¨C and now, quite possibly, yours. To learn more about the 4Cs, GIA, its reports and services, visit www.gia.edu World Headquarters | The Robert Mouawad Campus 5345 Armada Drive | Carlsbad, California 92008 T: 800-421-7250 | T: 760-603-4000 The World¡¯s Foremost Authority in Gemology? COPYRIGHT ?2006 GEMOLOGICAL INSTITUTE OF AMERICA, INC. ALL RIGHTS RESERVED. FC1106
  • 2. GIA 4Cs Color Clarity Cut Carat Weight Th e G I A C o l o r S c a l e e x t e n d s f r o m D The G IA Clarity Scale includes eleven Th e G I A C u t S c a l e r a n g e s f r o m E x c e l l e n t One carat equals 200 milligrams in weight. (colorless) to Z (light yellow or brown). clarity grades ranging from Flawless to I 3. to Poor. G IA provides a cut quality grade for For diamonds under one carat, each carat is divided into Although many people think of gem quality Because diamonds form under tremendous standard round brilliant diamonds that fall in the GIA 100 points ¨C similar to pennies in a dollar. 0.75 ct. = 75 diamonds as colorless, truly colorless diamonds heat and pressure, it is extremely rare to find D-to-Z color range. points, 1/2 ct. = 50 points. are actually very rare. Most diamonds used in a diamond that lacks any internal and external A polished diamond¡¯s beauty lies in its complex jewelry are nearly colorless with tints of yellow characteristics. These characteristics are a by- relationship with light: how light strikes the surface, or brown. product of its formation and help gemologists how much enters the diamond, and how, and in what separate natural diamonds from synthetics and form light returns to your eye. simulants, and identify individual stones. The result is a magnificent display of three attributes. 0.50 ct. 0.75 ct. 1.00 ct. 2.00 ct. 5.00 ct. Brightness is the combination of all white light reflecting from the surface and interior of a diamond. D H N Z Fire describes the ¡°flares¡± of color emitted from a diamond. Scintillation describes the flashes of Color grades are determined by comparing light you see when the diamond, the light, or the each diamond to a master set. Each letter grade observer moves. represents a range of color and is a measure of VVS 2 VS 2 A polished diamond¡¯s proportions affect its light performance, Beauty and Its Beholder The 4Cs provide a way how noticeable a color is. which in turn affects its beauty and overall appeal. Diamonds with to objectively compare and evaluate diamonds, but numbers fine proportions, symmetry, and polish optimize their interaction alone can¡¯t describe a diamond¡¯s mysterious with light, and have increased brightness, fire, and scintillation. and captivating beauty ¨C for that, you¡¯ll Fluorescence Some diamonds can emit a visible have to visit your local jeweler to see star length table size light when exposed to ultraviolet radiation, but one for yourself. crown fluorescence is not a factor in determining color girdle angle or clarity grades. However, a description of its SI 2 I2 thickness crown height strength and color is provided on GIA Reports Sample Clarity Diagrams total depth pavilion as an additional identifying characteristic. angle pavilion depth lower girdle/half facet length culet Anatomy of a Diamond