by uphone » Feb 26, 2019 Hey - So I'm working with a diamond wholesaler to find a stone. Based on my internet research, I found some ideal cut guidelines and calculators that are helping me weed out diamonds and trying to maximize performance. I understand that this process is highly subjective and there is no exact science, but as a person that does statistics for a living, it's hard for me not to ignore the guidelines and algorithms these "experts" have generated haha. The stone that my wholesaler found is slightly out of these "ideal guidelines" that I found on the internet due to the 59% table, 4.5% girdle thickness, and 1.01 l/w ratio. I recently saw a diamond in the store and my girlfriend was very happy with the size of 7.48 x 7.45. Are there any red flags from the specs of this diamond? Assuming the diamond is eye clean, does it look to be a good deal? Here are the GIA specs: https://www.gia.edu/report-check?reportno=3315878255&s=1551183901904 GIA #: 3315878255 Price: $10,800 Shape: Round Carat: 1.64 Cut: Excellent Color: H Clarity: VS1 Fluor: None Polish: Excellent Symmetry: Excellent Table: 59 Depth: 61.5 L/W Ratio: 1.01 Measurements: 7.56x7.49x4.63mm Crown Angle: 35° Pavilion Angle: 40.6° Girdle Thick: Sli. Thick Girdle %: 4.5 I used some online tools to evaluate: Enchanted Diamond Cut Score: 97.2 (Anything above 97.1 is their highest rating) Diamond Screener - On the edge of the intersection AGS and GIA Ideal StoneAlgo - Could not score the diamond HCA - 1.4 with Excellent for Light Return, Fire, and Brilliance and Very Good for Spread Rare Carat - 6/7 - Only issue they had was they wanted girdle to be 4.0% thickness or less and this is 4.5% Guidelines found from Price Scope: In general, you can use these parameters to find ideal cut stones: 54-57 table 60-62.4 depth (prefer <62) 34-35 crown (maybe 35.5, if paired with 40.6 pavilion) 40.6-40.9 pavilion (maybe 41, if paired with 34 crown) 75-80 lower girdle facets (many prefer 75 for fatter arrows & bolder flashes) Crown & pavilion angles must be complimentary. So a steep crown needs a shallow pavilion and vice versa. Some popular combos would be 35/40.6, 34/40.9 or 34.5/40.7 for example.