Diamond graders draw a diagram of the inclusions in the diamond (left) to a diagram (right) to create a map of the diamond’s inclusions, called the “plot”. The plot will be used to help the diamond lab give the diamond its final grade on the clarity scale.
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A stone plot on a diamond grading report is a bit like a fingerprint. It records the significant internal and external characteristics of the diamond as a way to help positively identify that diamond and justify its clarity grade. Every diamond is unique!
Translation plane
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Figure 4. This is how plots are traditionally oriented. Note that the feather in bezel #1 also breaks through the girdle to the upper half on the left #1 lower half.
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