Diamonds
Facts
Gemological Institute of America (GIA)
Contents of a GIA Diamond Grading Report
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Facts
- Diamonds are evaluated according to the 4Cs.
- CARAT - indicates a diamond's weight. The larger, the rarer it is.
- CLARITY - most diamonds have internal flaws known as inclusions caused by presence of traces of minerals. Clarity is graded based on number, size and type of inclusions. The fewer its presence, the more precious.
- CUT - how it is cut from the original stone. Qualities like roundness, depth, width as well as consistency of the faces.
- COLOR - the more valuable, the lesser the colour it has. Colour reduces the "fire" in the stone.
- Common diamond shapes are round, princesss, emerald, asscher, radiant, oval, pear, maquise and heart.
Gemological Institute of America (GIA)
- The Gemological Institute of America (GIA) was formed in 1931 and is an independent, non-profit, educational and research institution. The Institute's scientists, diamond graders, and educators are regarded as the world's foremost authority in gemology.
- GIA is the creator of the 4Cs of diamond value.
- The GIA does not buy or sell diamonds.
- A Diamond Grading Report issued by GIA, is recognized throughout the jewelry industry as the most respected, accurate and trustworthy grading report.
- Having a diamond certified by an individual who graduated from a course (e.g. the Graduate Diamonds diploma course) offered by GIA is NOT the same as having it certified by the GIA.
Contents of a GIA Diamond Grading Report
- DATE - Date of issue.
- GIA REPORT NUMBER - A unique identification number registered in GIA's global database.
- LASER INSCRIPTION REGISTRY - Diamonds may be micro-laser inscribed with the GIA Report Number.
- SHAPE AND CUTTING STYLE - Description of the shape of the diamond and the pattern on the facet arrangement (cutting style).
* Measurements - The "minimum diameter - maximum diameter x depth" for round shapes and "length x width x depth" for fancy shapes.
* Weight - Recorded to the nearest hundredth of a carat. One carat is equal to 1/5 of a gram.
- PROPORTIONS - Describes characteristics relating to the diamond's cut.
* Depth - Depth of the diamond relative to the average diameter for round shapes, or the width for fancy shapes.
* Table - The average size of the table facet in relation to the average diameter for round shapes, or the width of the table in relation to the width of the diamond for fancy shapes.
* Girdle - Range of girdle thickness relative to the size of the diamond, and condition (polished or faceted) if applicable.
* Culet - The size of the culet facet relative to the size of the diamond.
* Finish - The quality of the surface condition (polish) and the size, shape and placement of the facets, including the evenness of the outline (symmetry).
- CLARITY GRADE - Represents the relative absence of inclusions (internal characteristics) and blemishes (external characteristics). It is graded on a scale from Flawless to Included, based on size, nature, position and quantity of clarity characteristics observed under 10x magnification.
- COLOR - Assesses the absence of color from colorless to light yellow, brown or gray when compared to GIA Master Color Comparison Diamonds.
* Fluorescence - The strength and color of the diamond when viewed under long-wave ultraviolet light which is present in daylight.
- COMMENTS - Comments describe additional identifying characteristics or features that are not represented on the report.
- ADDITIONAL INSCRIPTION - Diamonds may be inscribed with a brand name, trade name or a personal message.
- GIA CLARITY AND GRADING SCALES - An illustration of both the GIA Color and Clarity Grade and their relative positions in the GIA Diamond Grading System.
- DIAGRAM - A diagram that shows the shape and cutting style of the diamond. Symbols on the diagram indicate the type of nature, position and approximate size of a clarity characteristic.
- KEY TO SYMBOLS - Lists the characteristics and symbols shown on the diagram, if present.
- SECURITY FEATURES - To ensure integrity, the GIA Gem Trade Laboratory Reports include a suite of security components. Notable features include a hologram, security screen, microprint lines and chemical sensitivity, in addition to several other proprietary security features.
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