English to German Tech/Engineering Mining & Minerals / Gems Schmuck, Schliff von Diamanten

Es geht um den Schliff von Diamanten und deren "Tiefe".

Der Kontext lautet:

"For several reasons: first of all, if the diamond is cut too deep, the light leaks out the diamond instead of being reflected back which causes it to look darker and more dull, this optical phenomenon is called “nailhead”.

On the contrary, should the diamond be too shallow, the girdle is actually reflected in the diamond and it causes the optical phenomenon called “fisheye”.

Obviously, even if a diamonds depth is excellent, if its ***table percentage*** and the angles are poor, the overall look of a diamond will be far from perfect."

Wie ist hier "table percentage" zu übersetzen? Ausgangswert? Ausgangsprozentsatz?

Bin für jeden Hinweis dankbar