possible for OMC to be round?

[LB123]

I am newly engaged (yay!), but there is a slight issue with my ring. It is from the 1920s. It''s description said that it was a GIA "certified" OMC stone. We''ve had it appraised somewhere else and it turns out the GIA report is for a RB stone. The store that did the appraisal said it is indeed an OMC stone. Now I''m concerned and don''t know who to believe!

The stone appears to be perfectly round and I can''t see an open culet. Is it possible that this is a OMC?

My FI will obviously be contacting the store to try to figure this out, but we''ve already had it sized. Not to mention I''m totally in love with it!!

Any help is appreciated.

 

[LB123]

Here is the only pic I can access at the moment.

 

[joxxxelyn]

I'm fairly certain it has a lot to do with the facet patterns.

 

[ChunkyCushionLover]

Date: 4/7/2010 2:17:54 PM
Author:LB123
I am newly engaged (yay!), but there is a slight issue with my ring. It is from the 1920s. It's description said that it was a GIA 'certified' OMC stone. We've had it appraised somewhere else and it turns out the GIA report is for a RB stone. The store that did the appraisal said it is indeed an OMC stone. Now I'm concerned and don't know who to believe!

The stone appears to be perfectly round and I can't see an open culet. Is it possible that this is a OMC?

My FI will obviously be contacting the store to try to figure this out, but we've already had it sized. Not to mention I'm totally in love with it!!

Any help is appreciated.

If that picture is accurate no it is impossible for the centre to be an Old Mine Cut. The outline is round and Old Mine Cuts or Old Mine Cushions were square or cushion shaped.

From GIA with my commentary:

Despite its use by trade, GIA has not used the term Old Mine Cut or Old Mine Cushion on grading reports in at least twenty years. An Old Mine Cut is a term applied properly to an early form of brilliant cut which was most common in the 18th century with nearly square or cushion shaped girdle outline. A term applied occasionally and incorrectly to a somewhat more modern style of brilliant cut that also has a much higher crown, smaller table than the modern brilliant cut but whose model outline is circular or approximately circular in a style of cutting that is more properly called a Lumpy Stone or an Old European Cut.

This Old Mine Cut was popular before the electric bruting machines were available and the outlines were not deeply or perfectly rounded as all cutting was done by hand. It will be very difficult to determine when a stone was cut and the piece produced (the setting will help a lot more than looking at the diamond), but in the 1920s OECs and Transitional cuts were available, the modern round brilliant was still not being produced.

In order for a stone to be considered an OEC or Transitional cut you would be looking for a high crown, small table, shorter lower girdle facets (fatter thicker arrows) and a culet. I would be cautious in even assuming the diamonds are even old without having an expert who is experienced in older cuts take a look.

None of this distracts from the beauty of the piece but I feel you should at least be informed and have it checked out by an experienced appraisor if the value, dating and naming of the diamonds are important to you.

 

[LB123]

I wouldn''t necessarily say the "naming" of the diamond cut is important to me, but I wanted an older stone and the seller claimed that this was an OMC. I would be disappointed to find out that this is a new RB stone placed in an old setting since it''s not what I originally wanted.

 

[ericad]

It's possible that the diamond is an Old European Cut. Impossible to say without a good face-up macro photo. An OEC is still old, but with a round outline and often a smaller culet. From your description it doesn't sound like an Old Mine Cut - some sellers call all old cuts "OMC" even when they are OEC's - happens a lot. It's also possible that your stone is a Transitional Cut or even a Round Brilliant. I wish I could be more helpful but I can't tell from the photo you posted.

Have you seen the ring in person? You said you love it and that's the most important thing, but I agree that it's important to know what you have! If you could post more photos, that would be helpful!

 

[Hest88]

Definitely see if you can get us a top-down picture of the stone. I loooove the setting, by the way, but it certainly doesn''t look like an OMC from this angle. However, a clear photo will allow us to give you feedback with 100% certainty.

 

[joxxxelyn]

As far as GIA, they still use the term "old mine brilliant," at least they did for this:

http://www.goodoldgold.com/diamond/6037/


But many of GOG vintage cushions have certs that say "cushion brilliant," so it''s hard to tell when or why GIA uses certain terms. It doesn''t appear to be extremely consistent, because one of their AVCs also said "cushion modified brilliant."

What I am trying to say is that I wouldn''t base it off the report. I would have it appraised.

 

[LB123]

Yes I''ve seen it briefly in person and do have some other pics I''ll try to post this evening. They are with a crappy point & shoot, so maybe not close enough, but I really appreciate you all trying to help me!

 

[LB123]

Well, they are probably too blurry for you to tell. But they are the best I can do for now.

 

[LB123]

One more.

 

[Hest88]

They''re fuzzy, but they have a chunky look to me that makes me think it''s an OEC or it could be a transitional cut. It doesn''t look like a modern cut diamond to me, but it''s certainly no OMC.

 

[heliotrope]

I would never claim to be an expert - but I have an OMC and it has a cutlet that is clearly visible when looking straight down into the table and the outline or shape looks a bit like a squished circle

looking at your pics - I would say yours is rounder and reminds me of a trasitional or oec - still old and stunning cuts

here are some diagrams I have saved whilst trying to learn about these older cuts - maybe they can help you with your stone

in regards to the certificate - I wonder if someone with a GIA cert for an oec or transitional can chime in as to the description used??

my stone is not GIA (shhh - don''t tell people around here!!) is was done by EGL (the LA lab) and I just noticed it is called a simple ''cushion''

your ring is stunning by the way - I hope you can find out the info you want to hear as obtaining an old stone was an important factor for me too

 

[ChunkyCushionLover]

Date: 4/7/2010 4:16:05 PM
Author: joxxxelyn


As far as GIA, they still use the term ''old mine brilliant,'' at least they did for this:

http://www.goodoldgold.com/diamond/6037/


But many of GOG vintage cushions have certs that say ''cushion brilliant,'' so it''s hard to tell when or why GIA uses certain terms. It doesn''t appear to be extremely consistent, because one of their AVCs also said ''cushion modified brilliant.''

What I am trying to say is that I wouldn''t base it off the report. I would have it appraised.

Joxxelyn,

I just submitted an article to PSAdmin on this very topic, i hope it will be helpful in clarifying the inconsistancy.
Stones with a round outline will never be called Cushion Brilliant, Cushion Modified Brilliant or Old Mine Brilliant on a grading report and have never been, those are reserved for cushion outlines containing corners.

Unfortunately trademembers and consumers often confuse Old Mine Cut and Old Mine Brilliant with Old European Cut and Transitional Cuts which is the source of confusion here. Sometimes retailers even confuse (often deliberately) an unsymmetrical modern round brilliant with an Old Mine Cut to romanticize a poorly cut stone as an antique when it may not be.

 

[512BB]

Date: 4/7/2010 6:24:14 PM
Author: heliotrope
in regards to the certificate - I wonder if someone with a GIA cert for an oec or transitional can chime in as to the description used??

Here is a GOG August Vintage Round (OEC) with a GIA cert that says round brilliant.

http://www.goodoldgold.com/diamond/6449/

As you can see on this one, AGS properly identifies the cut.

http://www.goodoldgold.com/diamond/7042/

 

[LB123]

Thank you all for your input!! I''m leaning towards it being a transitional since I can''t see a culet. We''ll contact the seller and see what he has to say when we get the appraisal report back.

I''ll try to post some clearer pictures this weekend.

 

[joxxxelyn]

ChunkyCushionLover,


I can''t wait to read your article. Like the OP, I also don''t care much about what a cut is called as long as I enjoy it and it''s well done. I just think it would be hard on GOG to have to send out all those beautiful stones that are so consistently cut, only to have them get different titles. I wonder what GOG thinks of getting back two AVCs that are both squared but labeled different cuts by the same lab. I love learning about different cuts and facets though. Keep sending more articles.