Does anyone know the ideal cut of a fancy yellow diamond. Is there a specfic table/depth #, to make it ideal?

Only round brilliant cuts have a strict cut grade system – the color does not matter when talking about Ideal cut. So if it’s any shape other then round brilliant, there is no ideal grading available.
In a round brilliant, the ideal proportions are:
Table diameter : 52.4 to 57.5%.
Total Depth : 59 – 61.8%
Crown Angle : 33.7 and 35.8% (perfect would be 34.5%)
Pavilion Angle : 40.6 – 40.9 degrees
Girdle : thin to meduim
Culet : pointy to very small

Hope this helps!

Fancy Cut Diamond
Fancy Cut Diamond
Fancy Cut Diamond