Clarity Plots and Comments
A comparison of the diamonds and the plots from all three labs showed that AGSL report plots had a consistency and greater degree of detail than the GIA-GTL reports. The plots of the EGL USA documents were close to the quality of AGSL and contained adequate detail. See Appendix V.
GIA-GTL made the most use of comments (12 clarity or surface feature comment on a total of 18 reports), followed by AGSL (10 such comments on 16 reports), however EGL USA made none. GIA-GTL’s stated practice is to plot only the marks that set the clarity grade, with others often being referred to in the comments section; this policy was reflected in the absence of a few inclusions which were reported in the comments section. GIA-GTL plotting was also somewhat less intensely drawn.