Help: GIA's cut shape naming conventions?

[Garry H (Cut Nut)]

I have seen people discussing Old Mine, OEC and transitional descriptions GIA use and what the differences are.
But overall I find the entire topic confusing.
Can you guess what a Cut-Cornered Square Modified Brilliant and a Cut-Cornered Rectangular Square Modified Brilliant? Or a Square Modified Brilliant Cut?
They were patented in 1977 and 1979 respectively, but GIA it seems, refuses to use any naming for any cut other than from more than 100 years ago. Even more recently invented and even trade marked diamond cuts.
To add to the confusion, in some cases GIA adds the term ‘Modified’ and other times simply leaves the term 'Brilliant' all by itself.
Take different patterns of marquise, pear and ovals for example?

 

[Karl_K]

It is confusing and its nutz how gia does it.
But transitional is not a gia term uses, and many diamond historians frown on it.
The only real transition in diamond cut happened with the invention and use of the diamond saw and even that is debatable because it took a few years to be adopted worldwide not coming into near universal use until after ww1.

All the rest are at best evolution or just changes in popularity of different proportion sets or facet designs.

Some consider the theft from the commons and the "its cut in diamond patents" with no credit to the original designers pushed by De Beers another transition point but it was more a business transition not a diamond cut transition because it failed and nothing new was created.
So in my opinion its in no way a transition point of diamond cut.

 

[Karl_K]

The most annoying thing gia does if they do not have a diagram that matches the facets on the stone it seems like they randomly pick one and it does not match the faceting on the stone.

 

[MollyMalone]

The most annoying thing gia does if they do not have a diagram that matches the facets on the stone it seems like they randomly pick one and it does not match the faceting on the stone.

Oh, THANK YOU so much for this! I'd noticed that, but thought I wasn't "reading" the diagram properly & felt stupid.

 

[Karl_K]

Oh, THANK YOU so much for this! I'd noticed that, but thought I wasn't "reading" the diagram properly & felt stupid.

Whats even more confusing is when looking at 2 stones with the same faceting have different diagrams and names neither of which match the stones faceting.

 

[Garry H (Cut Nut)]

Bump?

 

[Karl_K]

The reason GIA will not call branded cuts by their name is trademarks.
They would have to get permission to use them and when whatever protection expires would you give permission for your trademark to be applied to someone else's diamonds?

Is that what you were looking for Garry?

 

[Garry H (Cut Nut)]

The reason GIA will not call branded cuts by their name is trademarks.
They would have to get permission to use them and when whatever protection expires would you give permission for your trademark to be applied to someone else's diamonds?

Is that what you were looking for Garry?

If that was a valid reason, then how can we use names like radiant and princess Karl?
Those cuts were patented and have been out of patent for decades. As such I believe they can not be protected by trade marks.
So why can those names not be used on GIA grading reports?

Even stranger - IGI call a princess cut a princess but a radiant is a cut corner modified sq/rect brilliant.
@Rockdiamond David?

 

[Rockdiamond]

I agree that using the more common terminology formRadiant and process cut makes good sense….but…I think GIA wants to maintain some sort of “scientific“ terminology…..which relates to this

To add to the confusion, in some cases GIA adds the term ‘Modified’ and other times simply leaves the term 'Brilliant' all by itself.

ive actually found them to be pretty consistent in this regard. If the main pavilion facets are uninterrupted to the girdle it’s Pear, Oval, Heart , cushion brilliant. Added facets below the girdle that interrupt the facets, and GIA calls it modified.
Makes sense.

 

[diagem]

I believe its based somehow on the fact that "brilliant" faceting style means and adheres to the "standard"..., e.g. 57-58 facets total (excluding 90 deg. girdle facets).

If this was the case 100% of the time than I would be ok with it.., the problem arises when GIA gemmologists decide independently that some four or six fold pavilion styles still for some reason manage to earn the lone brilliant name. this is confusing and surprising as per GIA consistency capabilities.

From other labs mentioned I expect less automatically, just like with most of their "other" grading calls.