shape
carat
color
clarity

Pol & Sym in EC cuts ?

Status
Not open for further replies. Please create a new topic or request for this thread to be opened.

Ann

Brilliant_Rock
Joined
Sep 24, 2004
Messages
1,977
when looking online, how important is Polish & Sym. in Emerald Cuts ?

And does a small or even larger culet create another plane/table ?
 

Garry H (Cut Nut)

Super_Ideal_Rock
Trade
Joined
Aug 15, 2000
Messages
18,423
in any square shaped stone achieving excellent polish and symmetry can be impossible because they often must polish a facet close to the octahedral plane and this is virtually impossible sometimes no matter how competent the cutter and better quality wheels will not solve the problem.

Culets that are big enough to see are a problem - otherwise they can protect a stone from breakage during handling etc
 

kenny

Super_Ideal_Rock
Premium
Joined
Apr 30, 2005
Messages
33,227
Garry, what about those that got a GIA Excellent for polish and symmetry?

Does GIA have low standards if it is impossible as you say?

Or did you mean very difficult?

What do you think of the GIA standard of Excellent for polish and symmetry?
Too easy?
Too hard?

I'm asking because my asscher got Excellents, and I am wondering how meaningful they are.
 

Ann

Brilliant_Rock
Joined
Sep 24, 2004
Messages
1,977
ok, but is a small culet on a rectangular EC too big?
 

Garry H (Cut Nut)

Super_Ideal_Rock
Trade
Joined
Aug 15, 2000
Messages
18,423
On below 2ct it would be very hard to see a culet of Slightly large

Kenny re - read plesase
in any square shaped stone achieving excellent polish and symmetry can be impossible because they often must polish a facet close to the octahedral plane and this is virtually impossible sometimes no matter how competent the cutter and better quality wheels will not solve the problem.
 

strmrdr

Super_Ideal_Rock
Joined
Nov 1, 2003
Messages
23,295
My rule of thumb is that once it hits under VG then it needs to be looked at by a skilled and trusted vendor to see if its an issue or not.
It might or might not be.
In general to avoid hassles I recomend when having stones called in stick to VG/VG but if the vendor has a stone in stock below that and is in my opinion skilled and honest enough to say its not an issue then Id consider it.
 

strmrdr

Super_Ideal_Rock
Joined
Nov 1, 2003
Messages
23,295
culet - get pictures to see how it affects it.
small is usualy fine.

depending on size larger can SOMETIMES leave a line down the center of the stone that either windows or is dark and to me looks yucky.
 

Ann

Brilliant_Rock
Joined
Sep 24, 2004
Messages
1,977
the line down the center, that''s what I was wondering.

If the stone is a rect. EC say, around 4cts, would even a small culet be visible?
 

Garry H (Cut Nut)

Super_Ideal_Rock
Trade
Joined
Aug 15, 2000
Messages
18,423
small is under 3% of the width - so about (8mm wide x .03=) 0.024mm which would be I think too hard to see.

Can you give us a real world example? I think it is unlikely a cutter would make a diamond with a visible keel
 

strmrdr

Super_Ideal_Rock
Joined
Nov 1, 2003
Messages
23,295
Date: 12/3/2006 9:39:17 PM
Author: Ann
the line down the center, that''s what I was wondering.

If the stone is a rect. EC say, around 4cts, would even a small culet be visible?
get pictures and an IS or ASET image is prefered or see it in person.
There is no way you should buy such a stone without good pictures.
 

widget

Ideal_Rock
Joined
Nov 12, 2004
Messages
4,255
Ann....here''s the only picture I could find that clearly shows what the GIA called a "medium" culet on my EC. (It''s almost square, so it''s a ''short'' keel).

In real life, it''s an absolute non-issue...even with my glasses on!
5.gif


Do you have pictures of the stone you''re asking about?

BTW...my stone only has G/G P&S, and it looks great...

widget

3087hnnb1.jpg
 

Ann

Brilliant_Rock
Joined
Sep 24, 2004
Messages
1,977
No pictures, I am studying certs, pics, and the such right now.

I have seen some EC''s where the "keel" is very apparent and I wondered
if it was supposed to be that way.

When looking at EC''s, how should the corners look? Like a mass of sparkle
or angles coming together? I know that''s hard to describe, but I''ve seen both
and I wasn''t sure what was "right" or is there a right?

I am totally ignorant on EC''s, but I think I might look. Ok, here is a stupid question,
How many step cuts should there be - make sense? Bunches of little lines or 2 or 3 ?
I guess carat size makes a difference, huh?,
 
Status
Not open for further replies. Please create a new topic or request for this thread to be opened.
Be a part of the community Get 3 HCA Results
Top