HCA Question

[lstrgtrrz]

I have found a number of posts in which people suggested "ideal" ranges for a round diamond (table %, depth %, crown angle and pavilion angle). I have used those ranges to weed out a number of stones and then I run the best candidates through the HCA to further narrow the selections. I recently came across a diamond that has a couple numbers well outside the suggested range, yet it scores very highly on the HCA. Specifically, its table is 59% (I read that 53-58 is preferable) and a crown angle of 33.5 degrees (I read that 34-35 is preferable). The pavilion angle is 40.8, which is within the range I have been using of 40.6-41 and a depth of 60.5, which is within the range I have been using of 60-62.3. The HCA for this stone is 1.3, and is Excellent for Fire, Scintillation and Light Return and Very Good for Spread. Notwithstanding the excellent HCA score, is this stone less desirable because of crown angle and table percentage are outside of the "ideal" range? Or is it acceptable that the two "off" values appear to cancel each other out and result in an excellent HCA score?

 

[proto]

The hca says on the assumption that the report which provides the diamond dimensions are correct, a math calculation indicates that the diamond should have "good light performance" or bad light performance".

You cant tell till you look at an aset or idealscope.

Whether a stone is desirable or not is entirely subjective but usually depend on how shiny it is, linked to aset/idealscope