Ideal cut and hearts and arrows question

[calh22a]

Hi PSers. I hope this question isn't too noob, but can you have an ideal cut diamond (tolkowsky) that is not hearts and arrows? To my understanding, HA is due to facet symmetry and is independent of the diamond proportions. Is this correct? So would a ideal cut diamond with HA be more brilliant than an ideal without HA? I hope that wasn't too confusing of a post. Thanks for the help everyone.

 

[Lorelei]

Date: 1/9/2009 8:09:59 PM
Author:calh22a
Hi PSers. I hope this question isn't too noob, but can you have an ideal cut diamond (tolkowsky) that is not hearts and arrows? To my understanding, HA is due to facet symmetry and is independent of the diamond proportions. Is this correct? So would a ideal cut diamond with HA be more brilliant than an ideal without HA? I hope that wasn't too confusing of a post. Thanks for the help everyone.

H&A is due to optical symmetry amongst other factors, lab graded symmetry refers to the physical symmetries of a diamond - read more here.
http://diamonds.pricescope.com/symm.asp

The most important factors for light return are the proportions and angles of a diamond, not an arrow pattern - you can have a diamond with excellent proportions which is a top performer and h&a, you can also have a poorly cut diamond which isn't a good performer which shows arrows - and even a top performer which doesn't show arrows! So to answer your question highlighted above, not necessarily.

Further reading - http://diamonds.pricescope.com/hna.asp

 

[Allison D.]

Date: 1/9/2009 8:09:59 PM
Author:calh22a
Hi PSers. I hope this question isn''t too noob, but can you have an ideal cut diamond (tolkowsky) that is not hearts and arrows? To my understanding, HA is due to facet symmetry and is independent of the diamond proportions. Is this correct? So would a ideal cut diamond with HA be more brilliant than an ideal without HA? I hope that wasn''t too confusing of a post. Thanks for the help everyone.

Yes, it''s possible to have a diamond with Tolk proportions that doesn''t meet true H&A criteria.

The diamond may display a hearts-LIKE pattern, but it may not qualify as a true H&A if the pattern has a fault or lacks crispness.

 

[Paul-Antwerp]

Proportions are only averages of 8 angles.

Yes, you can have a stone with Tolkowsky-proportions that exhibits a H&A-pattern.
You can also have a stone with Tolkowsky-proportions that exhibits a pattern, close to H&A.
And you can also have a stone with Tolkowsky-proportions that exhibits no pattern at all.

Live long,