Stay away from Good Polish?

[j123]

I know there is no visible difference to the naked eye between VG and EX, but what about VG and good?

Would it be a mistake to purchase a diamond with good polish?

 

[stone-cold11]

I would, mainly because it is a mark of lack of workmanship of the cutter as it is relatively easy to get higher polish grade with the present tech.

 

[Karl_K]

good can be ok if it is vetted by a trusted expert not to have an ill effect face up and at a reasonable tilt.
It is more acceptable in fancies than rounds.
It mostly depends on which facet(s) it is that has the good polish.

 

[Dreamer_D]

Date: 3/18/2010 6:28:59 PM
Author: Stone-cold11
I would, mainly because it is a mark of lack of workmanship of the cutter as it is relatively easy to get higher polish grade with the present tech.

Ditto.

 

[Lorelei]

Date: 3/18/2010 6:35:35 PM
Author: Karl_K
good can be ok if it is vetted by a trusted expert not to have an ill effect face up and at a reasonable tilt.
It is more acceptable in fancies than rounds.
It mostly depends on which facet(s) it is that has the good polish.

Ditto.

More on polish here from the Pricescope tutorial.

 

[coati]

Date: 3/18/2010 6:21:38 PM
Author:j123
I know there is no visible difference to the naked eye between VG and EX, but what about VG and good?


Would it be a mistake to purchase a diamond with good polish?

Not necessarily. For example, white polish lines seen at 10X on a small portion of a couple pavilion facets will probably not affect the overall luster and appearance of the diamond. Those polish lines will, however, knock the grade down to Good.

With antique cuts good polish is par for the course, and it is not necessarily a detriment--the same goes for fancy shapes.

With polish, if you can't see it without magnification, then it most likely will not affect overall performance. Certainly not like fair or poor polish which will generally impact luster.

 

[diagem]

Date: 3/18/2010 6:28:59 PM
Author: Stone-cold11
I would, mainly because it is a mark of lack of workmanship of the cutter as it is relatively easy to get higher polish grade with the present tech.

Not necessarily a sign of 'lack of workmanship', too general a statement!
Diamonds is hard material and sometimes we (cutters) encounter material that simply cant be polished to high polish grades.
Also depending on the preliminary planning of the rough..., sometimes you are forced to plan the polished model within the rough at a tilt where some facets are parallel to the natural plane of the Diamond structure stopping a cutter from achieving good polish!

 

[stone-cold11]

ya, too general, I am talking w.r.t. round.

 

[Dreamer_D]

I guess with so many options I don''t see the need to drop to Good, though I suppose it could save some pennies. I was also thinking modern RBs when I thought about it.

 

[coati]

Date: 3/18/2010 8:06:50 PM
Author: Stone-cold11
ya, too general, I am talking w.r.t. round.

There''s a whole world of diamond outside of AGS 0 round brilliants.

 

[stone-cold11]

true, but what is the percentage of polish rounds compared to other cuts...

 

[Dreamer_D]

Date: 3/18/2010 8:18:33 PM
Author: coatimundi

Date: 3/18/2010 8:06:50 PM
Author: Stone-cold11
ya, too general, I am talking w.r.t. round.

There''s a whole world of diamond outside of AGS 0 round brilliants.

Whaaaa???

 

[coati]

Date: 3/18/2010 8:22:28 PM
Author: Stone-cold11
true, but what is the percentage of polish rounds compared to other cuts...

There are certainly more rounds cut than any other shape, but a Good polish grade doesn't necessarily equal a lesser cut or a lack of workmanship. The proportions (and relative angles) determine the life of a diamond, but you know that already StoneC.