These #'s don't seem to work

[tarams9]

Gem Scan Lab Report - Am I calculating the pavilion depth incorrectly? 43 depth + 1 girdle + 15.6 crown = 59.6 which HCA won't accept - yet this supposedly an ideal cut.

 

[Garry H (Cut Nut)]

Please use the angles.
I cant read them - but they are clearly there on the card.
Angles are much more accurate than pav and crown %.

 

[tarams9]

Sorry, the #'s are these (for a 1.11ct stone 6.65 x 6.61 x 4.10):

Table 57%
Crown Angle 36.30
Pavillion Angle 41
Girdle 1%
Crown 15.6%
Pavillion 43%

(They don't give an averall pavillion depth)

 

[yssie]

crown/pavilion angle combo does not look good

depth you want for HCA is overall stone depth, you have that in the stone measurements - 4.10/((6.65+6.61)/2) - 61.8%





ETA -
(tan 36.3deg)*[((AvgDiametre)-(0.57*AvgDiametre))/2] = crown height in mm = 1.05mm ~ 15.8%
(tan 41deg)*[(AvgDiametre)/2] = pav height in mm = 2.88mm ~ 43.5%

 

[tarams9]

I didn't know how to do that calculation - Thank you so much Yssie