If IGI grades slight flourescence [sic] in a diamond of G color. Is it actually going to be medium or even strong by GIA criteria? How does slight floures affect the price of a diamond.
  It’s very possible that an IGI “slight” fluorescence diamond would be graded “medium” by the GIA.  I would put the odds as follows for how the GIA would grade it: slight 25%, medium 60%, and strong 15%.  Slight fluorescence usually has no effect on the price of a diamond.
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