Professional Gem Sciences (PGS) is a full service gemological laboratory, offering independent, quality reports on diamonds and colored gemstones, whether loose or mounted in jewelry, for both the trade and private individuals.
PGS Cut Grade Parameters
| Lab | Professional Gem Sciences (P.G.S.) | |
| Cut > | Excellent Ideal cut | Premium Cut |
| Table width % | 53 - 57 | 52 - 61 |
| Crown Height % | 14.0 - 16.5 | 13.0 - 17.0 |
| Crown Angle % | 33.5 - 35.5 | 32.5 - 36.5 |
| Pavilion Depth % | 42.5 - 44.0 | 42.0 - 44.5 |
| Pavilion Angle | 40.5 - 41.0 | 40.25 - 41.5 |
| Girdle Thickness | Thin to Sl. Thick | Very Thin to Thick |
| Total Depth% | Not Addressed | Not Addressed |
| Culet size % | Pointed to Medium: Sl. Abraded | Pointed to Medium: Sl. Abraded: Sl. Nicked
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