Transparency in diamonds, and other C's

"Transparency matters Newman distinguishes between clarity - a stone's lack of inclusions and other blemishes and the first "T," transparency, which is how well it lets light pass While a diamond with high clarity will have few or no inclusions, a stone is transparent if a viewer can see objects through it distinctly Many laboratories don't take into account subtle differences in transparency, Newman writes.

"I've seen hazy and slightly cloudy diamonds with VS clarity grades," she notes in the book " I will mention again my dismay at GIA's (and probably other labs) that use the term 'Clouds' to describe diamonds that are translucent I see many of these diamonds from VS2 down that are 10x loupe clean but dull A decade ago I contacted Tom Moses, the boss of GIA grading business about an SI1 stone that was what many of you would call a fancy white diamond.

Here is his response: . Source