Poorly cut H&A image?

[About2ask]

does anyone have (or could maybe take) a picture of a stone that is graded as "fair" cut through an IS? I was just curious to see just how bad the hearts are and the arrows.

 

[stone-cold11]

here is a reference chart on IS interpretation. http://www.ideal-scope.com/using_reference_chart.asp

 

[About2ask]

Wow, haha, I have seen that image before and did not remember at all until now. Brain Fart!

 

[John P]

Date: 12/13/2008 4:50:21 PM
Author:About2ask
does anyone have (or could maybe take) a picture of a stone that is graded as ''fair'' cut through an IS? I was just curious to see just how bad the hearts are and the arrows.

Your thread title and first post are different requests.

The ideal-scope shows performance...The H&A viewer shows cutting precision...They are different things.

A diamond can have great performance without having great H&A precision.
A diamond with great H&A precision doesn''t necessarily have great performance.

Here are three IS images showing different levels of light return/performance (and crown cut precision).

 

[John P]

Regarding H&A images:

All three of these diamonds have good performance (AGS0 AGS0 GIA EX) but they have different appearances in terms of cut precision. Seen in a H&A viewer, left to right, I’d name them true H&A (cut specifically with H&A in mind), near-H&A (a ‘happy accident’ that wound up close - some sellers would add a H&A premium to these) and non-H&A (pretty obvious).

- Credit to Brian Gavin for the photos.

Many diamonds show decent arrows, since they’re comparatively easy to achieve; each arrow requires true alignment of only 2 facets. Each heart requires true alignment of 5 facets, so a diamond’s hearts can be distorted no matter how nice its arrows appear.

If H&A precision and the associated premium is important to you an actual hearts photo will be necessary to determine overall precision; it cannot be determined from the arrows view alone.