Stones in this category are free from internal and external blemishes when examined by skilled observation in natural or artificial light with a 10X loupe corrected for chromatic and spherical aberration or with a 10X binocular microscope equipped with dark field illumination. The following conditions will not remove a stone from the flawless grade:
1) an "extra facet," located on the pavilion, which cannot be seen from the face up position.
2) a "Natural" that does not extend beyond the maximum width of the girdle or break the symmetry of the girdle line, and which cannot be seen from the face up position.
3) internal graining which is niether reflective, whitish, colored nor significantly affecting transparency.
The stone usually displays a wonderfully clean, icy appearance.
(at 30X, characteristics are difficult to see and locate.)
This clarity grade range is most commonly sought after by investors, as it demands an extremely high price per carat, while producing the highest yield in increased value over the long term.