The key to determining the type of clarity characteristics within a lab graded diamond is contained within the plotting diagrams which appear on the lab report. The top half of the diamond is represented by the diagram pictured on the left and the lower half of the diamond is represented by the diagram pictured on the left. Inclusions will be indicated on the section of the plotting diagram where the inclusion is located and not necessarily where it is visible from. Thus an inclusion may be indicated in the lower half of the diamond as is feather indicated by the green arrow in the diagram provided, but may be apparent from a top down view because the facets of a diamond are essentially tiny windows that make it possible to see inclusions from a variety of vantage points. Beneath the plotting diagram on a GIA diamond grading report there is a "key to symbols" which indicates the type of inclusions contained within the diamond. On AGS graded diamonds the key to symbols is usually located on a flap which is folded beneath the report when it is placed in its folder.

To align the top and bottom portions of the plotting diagrams, imagine a dotted line running vertically between the two halves. If you were to fold the bottom half (right side) of the plotting diagram on the dotted line and fold it under the top half, that is the correct alignment for the stone. Thus the three o’clock position of the bottom plotting diagram aligns correctly with the nine o’clock position of the upper plotting diagram. With this alignment in mind, it is easy to determine the proximity of inclusions plotted on the upper half of the plotting diagram with those that might be indicated on the lower half and vice versa.

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