what makes a bad cut?

[radiantquest]

are diamonds that have inclusions in certain spots the reason for bad cuts? is it inexperience that makes a bad cut? is it laziness?

why are bad cuts even done?

 

[stone-cold11]

Mostly to retain weight as diamonds are priced primarily by their weight.

 

[Todd Gray]

Date: 6/30/2009 4:39:22 PM
Author:radiantquest
are diamonds that have inclusions in certain spots the reason for bad cuts? is it inexperience that makes a bad cut? is it laziness?

why are bad cuts even done?

IMO it is because precision cutting costs more in terms of production cost (planning, cutting, polishing, etc.) than cutting a diamond for maximum weight retention. And let''s face it, since diamonds are sold by carat weight and Priced Per Carat (PPC) or Price Carat (PC) the more a diamond weighs, the more the cutter is going to yield from it.

And of course there is always the matter of skill and talent, the reality is that the guy who produces a round brilliant cut diamond which has a proportions rating of AGS-10 Very Poor and a polish rating of fair to good is probably not capable of producing a zero ideal cut diamond with AGS Ideal 0 proportions, polish, symmetry, light performance without more skill and experience.

 

[radiantquest]

so what you are telling me is that it is a mix of lack of skill or inexperience and greed? wow.

so diamonds are mostly priced on carat? i would think that a .85 with a superior cut would make more money than a .90 with a fair cut. hmmm.

also when cutting a diamond what is done with the left overs. i mean obviously if it was a big rough and there were large pieces left behind they would be cut themselves. are smaller ones then used for pave and then melee with diamonds and then the even smaller pieces used for industry. like you hear about saw blades and i think i have even heard of sink faucets with tiny diamonds used where the water comes out. i guess i am just curious what happens to the very small diamonds and chips.

 

[stone-cold11]

There is a sharp price jump at certain carat range, so bad cut commonly happen around that range also, to hit the threshold for the price/carat jump. For example, 0.5c, 0.7c, 1.0c, 1.5c. Those slightly below are generally better cut as the cutter are trying to get the premium due to Ex/Id cut rather than through weight.

I think smaller usable rough are sold to other cutter or cut by the vendor themselves into smaller pieces and finally to melees. Not sure what they do with the chips being polished off though.

 

[Todd Gray]

Date: 6/30/2009 4:53:16 PM
Author: radiantquest
so what you are telling me is that it is a mix of lack of skill or inexperience and greed? wow.

so diamonds are soley priced on carat? i would think that a .85 with a superior cut would make more money than a .90 with a fair cut. hmmm

Surprisingly I think that the diamond cutters with the most skill likely make less $$$ on the diamonds they sell than diamond cutters who sell Drek. But then again, in our industry there is more profit in terms of percent on a $25.00 silver chain than there is on a diamond in my experience.

Diamonds are not sold solely by Carat weight, the other factors Cut (quality, not shape*); Color; Clarity... And then there are different price per carats charged for different shapes because different diamond rough is used to produce different diamond shapes...

A well cut 0.85 carat diamond might make more money than a poorly cut 0.90 carat diamond, but the answer is not that simple... There is an increase in the price per carat that occurs between the 0.89 - 0.90 carat marks and the 0.99 - 1.00 carat marks and so on - this is part of the challenge because if a cutter is evaluating a three carat piece of diamond rough, part of that evaluation process takes the potential yield of the diamond into account (to the extent that there are computerized evaluation systems that will help to estimate the yield given 2 - 3 different cutting scenarios / proportions). So the cutter is looking at the piece of diamond rough and he concludes that it will yield either a spectacular round brilliant ideal cut diamond weighing 1.38 - 1.42 carats finished -or- it can be cut to yield a 1.75 carat round of good to very good cut... There is a major increase in the PPC between 1.49 - 1.50 carats and then more subtle "invisible" increases that are going to occur at the 1.59 - 1.60 / 1.69 - 1.70 marks, guess what most cutters are going to produce?

And it''s not really a matter of greed, sometimes it is simply a matter of economics and their placement in the market, market demand and all that... Various automobile manufacturers produce a variety of models and qualities based on market demand and the economic needs of various consumers, I suppose that not everybody finds an ideal cut diamond as beautiful as I do, there are people who might prefer the visual properties of a diamond which is "steep / deep" IMO or "shallow and spread". To each his / her own and all that.

 

[Lorelei]

Date: 6/30/2009 4:48:21 PM
Author: Todd Gray

Date: 6/30/2009 4:39:22 PM
Author:radiantquest
are diamonds that have inclusions in certain spots the reason for bad cuts? is it inexperience that makes a bad cut? is it laziness?

why are bad cuts even done?

IMO it is because precision cutting costs more in terms of production cost (planning, cutting, polishing, etc.) than cutting a diamond for maximum weight retention. And let's face it, since diamonds are sold by carat weight and Priced Per Carat (PPC) or Price Carat (PC) the more a diamond weighs, the more the cutter is going to yield from it.

And of course there is always the matter of skill and talent, the reality is that the guy who produces a round brilliant cut diamond which has a proportions rating of AGS-10 Very Poor and a polish rating of fair to good is probably not capable of producing a zero ideal cut diamond with AGS Ideal 0 proportions, polish, symmetry, light performance without more skill and experience.

Ditto Todd. And as with any highly skilled job, there are some who are far better at it than others, same with diamond cutters.

 

[strmrdr]

Todd is right but it goes one step back the chain also.
Rough is sold by the potential yield.
If the seller of the rough priced or the bid prices reached a point based on so-so cut over a magic number then a cutter can''t cut an ideal cut diamond that doesn''t reach that number out of it and make money.