Hi Sam,

Would like to know if a diamond marked with H/A means that it is a prefect cut diamond?.
Also if the diamond has 3Ex cut grade does it means it is a prefect cut diamond?

Is a prefect cut diamond has the best 亮光和火彩 or prefect cut diamond can still look dull

If H/A or 3 Exe diamond does not mean it has the best 亮光和火彩,  Should we only depends on the cut ratio of following seven criteria in order to determine which diamond has the best 亮光和火彩
   
七个切割比率，包括：台宽比、冠高比、腰厚比、亭深比、底尖比、全深比、冠角比. much appreciated if you can provide the ideal ratio of each items

Thanks

sam

hi，


如果鑽石是八心八箭和CUT GRADE 是EX,這粒鑽石對稱性,火彩會較平均.
八心八箭要自己用小儀器檢測,就很簡單會知道有沒有八心八箭,
H/A是鑽石加工廠自己評估,GIA是沒有評級是否H/A.
如果你想在嚴格些想找一粒更高標準的鑽石，你可以參考下IDEAL CUT 數據，
他會更加清楚數據範圍，但有些數據沒有寫下，我在補充些，
7) Star facet 50-55%
8) Lower Girdle facet 80-85 %

http://www.jewellerycatalogue.co.uk/diamonds/ags_detail.php

THX

SAM