The Prestige Report™ with Grading
A further level of reporting to the Prestige Report™ can involve the addition of a full grading analysis. AGL's full grading analysis will assess the gemstone's color, clarity and cut as well as other factors that impact the overall quality of a colored stone. When grading is added to a Prestige level Identification and Enhancement or Geographic Origin report, the stone will receive the industry's most complete assessment of the factors that have the greatest impact on a gemstone's value.
For samples and a complete breakdown of our Grading Report, see below.
The Prestige Report™ with Grading, no Origin
Seen above is the Prestige Grading Report without origin on bi-color stone. We do not offer origin on topaz.
The Prestige Report™ with Grading & Origin
The top section that addresses the Full Grading of a gemstone, addresses the factors related to the gem's color appearance.
Color Grade & Color Rating Range - The AGLcolor grade and color rating range is a two-part description that defines the specificcolor of your gemstone. AGL has simplified the description of color by combining the two essential color components of hue and saturation into a Color Rating category. This color component is a numerical representation ranging from 1 to 10 and describes the quality of the color. The second numeric reference describes the tone or lightness-darkness of your gem. Tone is represented as a percentage ranging from 0% (white)to 100% (black). In total, the color grade indicates the average quality of the color, while thecolor rating range describes the full range that may be visible in a gem’s normal viewing position.
This stone displays moderate color zoning, in the first position.
Color Zoning and Bichroic Effect - Not all stones exhibit uniform coloration. Color zoning and cutting can produce color variations that affect appearance and visual color uniformity. The obviousness of these variations is described in terms of faint, moderate, strong and prominent. A numeric superscript indicates the direction in which this effect is most visible. Direction 1 is the face-up viewing position. Direction 3 is visible through the side, approximately 90 degrees to the table facet. Whereas direction 2 is an intermediate viewing position between 1 and 3.
This stone displays a bichroic effect, as seen here at Direction 2.
Light Source - The color of a gem can varyaccording to the lighting environment in which it is viewed. To maintain consistency, AGL uses a standardized lighting environment to evaluate the color of all gems.
The second section from the top addresses the factors involved in determining a gemstone's clarity.
Clarity Grade - AGL clarity judgements blend the size, nature, number, location and impact on durability of the internal and external features of a gemstone under 2.5x magnification. Clarity grades include ten essential categories ranging from Free of Inclusions (FI) Lightly Included (LI1 and LI2), Moderately Included (MI1 and MI2), Highly Included (HI1 and HI2) to Excessively Included (EI1, EI2 and EI3).
General Texture & Reflective Texture - Gemstones may exhibit textural characteristics that may reduce the overall transparency of a gemstone or reflect light. General Texture relates to the general presence of inclusions across the face-up appearance that impact the transparency of a gemstone, but do not necessarily stand out as individual inclusion features. Reflective Texture relates more specifically to inclusions that reflect light back to the eye of the observer, such as rutile silk in a ruby or sapphire. AGL describes the presence and impact of texturing in terms of faint, moderate, strong and prominent.
The third section of the grading column addresses the factors related to the cutting of a gemstone.
Cutting Grade & Finish Grade - The AGL Cutting Grade evaluates the proportions and geometry of the gem’s shape and cut. The AGL finish grade describes the finer details of symmetry and polish. The grades are described using a numerical reference scale from 1 to 10 and an accompanying verbal description.
Brilliancy Range & Brilliancy Average - Brilliancy refers to the ability of a gem to reflect and return light back to the observer’s eye in the face-up position. This information is provided as a percentage or a percentage range of light returned to the eye estimated from the girdle to the culet or keel of the gemstone.
Depth Percentage - This calculation indicates the mathematical relationship between the width and depth of a gem expressed as a percentage and is directly related to the brilliancy of your gem.
The bottom section of the grading column is a summary assessment of all the factors that influence the overall quality of a gem.
Total Quality Integration - The Total Quality Integration Rating (TQIR) is a summary of the overall quality of your gemstone in its size category. All of the factors that contribute to the overall quality and rarity of a gem are combined into this easy-to-use & understand statement.
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