« GIA Announces Membership Changes. | Main | An Expensive Diamond Two-Timer! »

Round Brilliant Diamond Shape: Some Notes.

GIA updated the wording and the placement of “brillianteering” comments on its Diamond Grading Report and Diamond Dossier® for standard round brilliant diamonds as of July 1, 2006.

GIA’s new Diamond Grading Report and Diamond Dossier®, in January 2006, indicated when a diamond’s cut grade was affected by painting or digging out by putting a notation within the report’s comments section that read: Cut grade is based on brillianteering of the half-facets.

As of July 1, this statement will be located under the proportion diagram –-not in the comments section-– that reads: Cut grade affected by brillianteering.

Brillianteering refers to the last steps of the polishing process when the star facets along with the upper and lower half facets (also known as upper and lower girdle facets) are polished on the diamond. When a diamond is painted or dug out, these facets are polished in a manner that can affect the face-up appearance of the diamond and therefore may affect the final cut grade.

New Area For GIA Brillanteer Comments.jpg
New location for comments on Girdle thickness.

Here is an illustration of an even and correctly proportioned girdle.

Normal and Even Girdle

Here is an illustration of a "dug out" girdle. Note the uneven and very thin areas. This is usually done in situations where there may be large naturals, indented naturals, large imperfections,or other problems such as difficult cutting grains that the manufacturer needs to better control in order to save weight and/or make the diamond more saleable This may at times come at the expense of Symmetry in that facets are mis-aligned. This can also have a significant negative effect on light performance.
Dug out girdle

Here is an illustration of a "painted girdle". Note the extra thickness at the meet points of the upper to lower half facets These facets are cut shallow with a minimum of definition and resolution, hence "painted" onto the diamond so that the cutter can retain maximum carat weight.

May or may not have a negative impact on light performance and physical evaluation or additional information such as a Gemex Brilliancescope Light Analysis Report and Imagescope can be very helpful.
Painted Girdle

And just to review for newcomers to our DiamondVues Blog, the illustration below shows the various facets that comprise the round brilliant diamond shape. In all, there are 58 facets for the round diamond.
diamond anatomy.gif


Posted by Barry Gutwein on July 7, 2006 3:54 PM in Diamond Basics | Comments (25)

Comments

Attractive section of content. I just stumbled upon your web site and in accession capital to assert that I get in fact enjoyed account your blog posts. Anyway I will be subscribing to your augment and even I achievement you access consistently fast.

There is a less invasive treatment to migraine headache. Finding out about the causes is really important.

Been reading this blog for a few days now. It was high quality and solid information. BTW, I like your blog design as well. I liked reading it and hopefully you will post more soon. Do you have a twitter page?

Good site. You definetivly know what you are discussing about here. I am so glad I was able to discover your blog post. I look to see more great writing from you. Keep up the awesome work

Hi there. This is a remarkable web page. I will e-mail this to my coworkers. I found this post while exploring on internet. I'll be sure to come back. thanks a lot for publishing.

This blog is fairly interesting. I am glad I found it because I discovered great tips as I read it. Keep posting.

I was reading your website and I entirely relate to what you are saying. Keep publishing.

Hey there. This is a formidable blog. I will e-mail this to my coworkers. I found this website while searching on internet. I'll be sure to come back. thanks a lot for publishing.

A few days ago I came across this page and have enjoyed the info. I look forward to long term tips and can without doubt link to this and inform the people. Thanks a lot.

I have found that blog and if I might I would like to brief you some worthy idea. Maybe you can publish more posts reffering to this one. I would like to read some more about it!

I have been exploring online more than 5 hours today, yet I never discovered any engaging website like yours. It's pretty worth substantial for me. Personally, if all web owners and bloggers made good content as you did, the web will be much more advantageous than ever before.

You came up with some new points there. I did a search on the keyword and discovered nearly all individuals will agree with your article.

Hello, i would like to tell you thank you very much for giving us that very instructive post. it is really a to a degree interesting blog post.

Hello. Great website. Thanks for taking the time to share your ideas with the web community.

It is my pleasure to come by your blog and to enjoy your articles. All of them make sense and are very worthy. Best regards.

I have discovered that website and if I might I would like to submit you some beneficial idea. Maybe you can write more articles reffering to this one. I would like to read some more about it!

Advantageous info and great template you got here! I want to thank you a lot for sharing your tips and taking the time into the stuff you publish! Sublime work!

I was reading your blog and I totally agree to what you are discussing. Keep publishing.

Great post?-.plz assistance me i also choose to publish here?-.

i may well not agree with everything that is l isted because the best and worst logos?-but i confident loved studying about them and i really like the backwards and forwards d iscussions about the l ists. it is great to view some passion inside design group!

You really allow it to be seem so easy together with your presentation but I've found this topic to be actually a thing that I think I'd never understand.

Zune and iPod: Most people compare the Zune to the Touch, but after seeing how slim and surprisingly small and light it is, I consider it to be a rather unique hybrid that combines qualities of both the Touch and the Nano. It's very colorful and lovely OLED screen is slightly smaller than the touch screen, but the player itself feels quite a bit smaller and lighter. It weighs about 2/3 as much, and is noticeably smaller in width and height, while being just a hair thicker.

a very good weblog post ,We stock Argyle, Bailey, Cardy, Sheepskin, ?- .

You actually make it seem very easy with your presentation but I find this topic to be actually something which I believe I'd never understand.

Good way of puttin it..

Post a comment