HCA and Early Round Brilliants

[Luminous1]

I purchased a stone that is obviously an older cut stone. It has a GIA report stating it is a round brilliant but I know their classification of old European cut is rather strict. I thought it was probably a transitional but I know that category is rather nebulous also. I took it to be appraised and the appraiser stated that he believed it to be an early round brilliant cut. The GIA report has all the angles ,etc listed and I knew it was a bit funky but I wasn’t expecting it to be an early round brilliant cut. I ran it through the HCA and it comes back at 5.8. My question is whether or not the HCA would apply to these early round brilliant cuts. I like older cuts and I know their performance isn’t going to be apples to apples equivalent but I also don’t want a fair to middling cut stone. Here is a snippet from the GIA report.


The stone is a nice bright white clean stone. It does sparkle nicely but I would not be able to rank it. (Oh- and I am still within the return period.)

 

[rockysalamander]

Hca is for modern round brilliant only. Not trannys.Can you post a picture that shows the faceting?

 

[John P]

Different category. This is a cousin to antique makes which were developed prior to electric lighting. They're characterized by wider pavilion mains for broad spectral fans and higher crowns creating more room for dispersion. This one has a characteristic thin girdle and open culet too (polished flat so the point didn't stab the wearer's finger). These makes maximize dispersion by increasing the size of the virtual facets, without the aid of modern tools or modeling. The cutting goal was not light return, it was all about refraction. In fact, use of the term "fire" to describe refraction originated in that era The description was literally about maximizing the reflection/refraction of the fire coming from the gas lamps under which diamond cutters worked in those days.

 

[Luminous1]

Hca is for modern round brilliant only. Not trannys.Can you post a picture that shows the faceting?

Here is a photo from the appraiser. My phone is refusing to focus on it.
It is eye clean- that black spot is not there in person. I'll try again later tonight when my kids are asleep

 

[ChristineRose]

Not that you can really tell from a picture, but that looks pretty well cut.

OEC are round brilliants. They are round, and the brilliant part means that they have the cross faceting as opposed to being single cuts. That may be part of the confusion.

 

[Luminous1]

Different category. This is a cousin to antique makes which were developed prior to electric lighting. They're characterized by wider pavilion mains for broad spectral fans and higher crowns creating more room for dispersion. This one has a characteristic thin girdle and open culet too (polished flat so the point didn't stab the wearer's finger). These makes maximize dispersion by increasing the size of the virtual facets, without the aid of modern tools or modeling. The cutting goal was not light return, it was all about refraction. In fact, use of the term "fire" to describe refraction originated in that era The description was literally about maximizing the reflection/refraction of the fire coming from the gas lamps under which diamond cutters worked in those days.

Thank you for explaining that to me. I find the history of these diamonds fascinating.

 

[Luminous1]

Here's a much better picture. I figured out to use the loop so it is less sharp than in person.

 

[LightBright]

It looks like an American Cut, some people would call it a Transitional. I think it is a very pretty, well cut stone for its time. HCA score simply means what John Pollard says. Your stone was not cut for light return, it was cut for refraction. Hence it will look awesome in candlelight. I own one of these and the setting it’s mounted in says 1913. So not necessarily more modern than OECs. Look up Deamer’s “one ring to rule them all George” for a discussion on the cut. I believe your stone is similar to hers. Here’s a link to her discussion on her stone’s dimensions, but read all ten pages for detailed discussion and similar cut stones. https://www.pricescope.com/community/threads/my-dream-ring-8-1mm-european-cut-diamond.177658/page-5

 

[SimoneDi]

It looks like a transitional cut to me. I love the pattern, the open culet and the overall make! If you don’t mind sharing, how much did you pay for the stone? I think that will help the old it experts chime in regarding “value”. I think that your stone is gorgeous!

 

[LaylaR]

Oh yeah. I love that faceting. Of course it's similar to the one my personal stone has. I'd call it a transitional. And a nice one with a high crown (many transitional have flatter crowns, including my own) nice table size. The thin girdle is also characteristic. And so it the small culet and the arrows under the table with the snowflake patterning.

You don't treat these like a MRB when you are evaluating them. You treat them like fancies.

This picture What do you plan to do with it?

 

[Luminous1]

Thanks everyone. The appraiser just kept describing it as "good". I think he was evaluating it like it was a modern round brilliant. Is a picture of the stone and the words "early round brilliant" enough of a description for insurance?

 

[Luminous1]

Thanks!!! I'm planning on setting this into an engagement ring- it's my upgrade stone. I've just got to decide on a setting. Most of the budget went to the stone so my options for a setting is a bit more limited.

 

[ringo865]

Wow, what a beautiful stone! Would you post a profile pic? (of the stone )

 

[Luminous1]

Wow, what a beautiful stone! Would you post a profile pic? (of the stone )

Here you go.... I'm holding my finger over a small led light- hence the orange color.

 

[flyingpig]

Lovely

 

[LaylaR]

Thanks everyone. The appraiser just kept describing it as "good". I think he was evaluating it like it was a modern round brilliant. Is a picture of the stone and the words "early round brilliant" enough of a description for insurance?

I'm not an appraiser or even a GG, so take my advice with a grain of salt. But I would want more than that. I would want multiple images, I would want comments about the faceting, and the fact that it's considered a transitional cut.

Most appraisers are not very good. I would take the extra time to send it to Old Miner or Neil, personally, and pay to have it professionally appraised.

If you suffer a loss you want a bullet proof document. I speak from personal experience.

Regarding settings. You are in great hands. These ladies and gentlemen are absolute CHAMPS at finding budget settings that will knock your socks off if you keep your desires realistic (no platinum double halos a la Tiffany on a $500 budget). Post the following information: Diamond DIAMETER (not just the weight), budget (including any setting fees and tax), finger size, and what you want, what is most important to you.

Also get your stone insured before setting it. Do a search on here for further explanations on that.

 

[EvaEvans]

Keep this stone! It's beautiful!

 

[Karl_K]

My guess is 40/40 cut late 1800s to early 1900s cut in Europe or a more modern replica.
The girdle has likely been repaired at some point over the years.

 

[Karl_K]

Based on the listed proportions this is the expected ASET, I would love to see a real ASET image of it.
For the lighting of the day this would have to be considered extremely well cut based on the type of light and the general direction the light would hit the diamond.
Understanding these cuts the lighting of the day must be the primary condideration.

 

[Karl_K]

40/40 angle combination goes back to some of the earliest cut diamonds.
They are called that because of the 40 degree crown angle and 40 degree pavilion plus or minus a few degrees.

 

[Karl_K]

Too help marrow the date down what are the symmetry and polish grades?

 

[Luminous1]

Too help marrow the date down what are the symmetry and polish grades?

They are both listed as good.

I've never heard of the 40/40 diamond. I'm really loving learning about this.

 

[valeria101]

@Karl_K

Love such patchwork contrast patterns in the RBC ... (proportions, TBD)

Ought to breed more of the species !

Just a thought

 

[Maggiemeans]

I have to tell you, I don't know much about older diamonds.. and only go by what speaks to my heart.. but this stone has me at hello. I love your stone! It really is pretty and has personality. Looking forward to following the rest of your ring journey!

 

[Karl_K]

They are both listed as good.

I've never heard of the 40/40 diamond. I'm really loving learning about this.

That is an indication it may well be old.
If it was EX/EX then it would point to it possibly being more modern.
It is still not impossible that it is fairly modern, but its an indication that it may well be old.

 

[Karl_K]

@Karl_K

Love such patchwork contrast patterns in the RBC ... (proportions, TBD)

Ought to breed more of the species !

Just a thought

Cut grading killed any chance of that happening.
Both the GIA and AGS systems hammer it even though it might be better than some combinations scoring much higher.

 

[rockysalamander]

Cut grading killed any chance of that happening.
Both the GIA and AGS systems hammer it even though it might be better than some combinations scoring much higher.

Such a shame. I love stones like this...I never knew my jeweller-grandmother to use the term 40/40, but it was one of the patterns she really favored. She referred to it as a petticoat OEC. I suspect many of the OECs have "common names" that folks have invented.

 

[John P]

The below was one of the first devices to regulate 'angles' in the 1800s. It's a simple brass plate with a hinged bar extended at 45 degrees (graphic from 'American Cut' by Al Gilberston).

Many operations had cutters follow these crude angles, in essence making the rough goal (pun intended) 45/45.


Add to this that table facets were originally fashioned by grinding material down, resulting in tiny tables by modern standards... 45/45/45 n'est ce pas?

Grinding is also the reason many antique cuts were squarish. If a cutter wanted to make a diamond round the corners had to be ground away, as well as the top. Since compensation was higher for higher finished weight, the final shape of most diamonds was dictated by the shape of the rough and how much it would yield.

The introduction of the rotary saw, circa 1900, changed everything. Now instead of grinding one diamond from a standard rough, it was possible to saw away a 'toppie' and produce two diamonds from that rough. This windfall for cutters was short-lived, however. By 1902 DeBeers (nee The Syndicate) had reacted by hiking the price of rough 30%... Plus ça change, plus c'est la même chose.

 

[Karl_K]

Such a shame. I love stones like this...I never knew my jeweller-grandmother to use the term 40/40, but it was one of the patterns she really favored. She referred to it as a petticoat OEC. I suspect many of the OECs have "common names" that folks have invented.

It may be and most likely is a some what modern descriptive term rather than a name used back in the day.
I picked it up on some website years ago and Al Gilbertson mentions them in his book but does not call them 40/40 cuts that I recall.
https://www.pricescope.com/communit...irst-100-years-al-gilbertson-free-pdf.228643/

I think you are correct, there are many "common names" in diamonds and jewelry.

 

[John P]

It may be and most likely is a some what modern descriptive term rather than a name used back in the day.
I picked it up on some website years ago and Al Gilbertson mentions them in his book but does not call them 40/40 cuts that I recall.
https://www.pricescope.com/communit...irst-100-years-al-gilbertson-free-pdf.228643/

40/40 and 45/45 are good nicknames but not commonly used descriptions such as Tolk or 60/60.

That link is a great resource. Check pages 31-39 RE mechanical bruting and angles.