Tiffany cert. vs. Diamond Calculator on Pricescope

[lisa1.01fvs1]

When I plugged in the numbers of my diamond from Tiffany Cert. here on Pricescope it came up saying my stone was a "2.5 and very good"!!!!!

The cert. says cut, polish, symmetry ALL Excellent. HUH?

Any ideas?

 

[lisa1.01fvs1]

Sorry I used the Holloway crown and pavillion angles...........

 

[Garry H (Cut Nut)]

Better than average for Tiffany

Here is somoene elses experiance a few months ago

https://www.pricescope.com/community/threads/a-day-at-tiffanys-with-the-i-scope.69733/

 

[whitedragon]

Lisa,

I''m a bit new here myself, but I believe the HCA measures light return based on angles and table and depth %--whereas "cut" as defined on your cert is how well what AGS, GIA, (or whoever else) felt that the diamond cutter did on your stone. As such, you''ll note that on the HCA page is mentioned that it cannot account for symmetry and polish as it has no idea. This being said, your diamond''s actual polish and symmetry are going to tell the real tale.

HCA is just meant to help people weed out potentially poor-performing stones. If you already have yours and it performs well, then I don''t think you quite have much to worry about. : )

Hope this helps a bit?

 

[JohnQuixote]

Date: 1/24/2008 2:44:15 AM
Author:lisa1.01fvs1
When I plugged in the numbers of my diamond from Tiffany Cert. here on Pricescope it came up saying my stone was a ''2.5 and very good''!!!!!

The cert. says cut, polish, symmetry ALL Excellent. HUH?

Any ideas?

Tiffany cuts nice diamonds. They tend to fall a bit deep of center in our common cross-pollination of PS metrics (GIA, AGS, AGA, HCA) whereas the HCA tends to the shallow of center. As Garry said, 2.5 is rather good. It means your diamond didn’t have home-field advantage and still scored well.

 

[JohnQuixote]

Date: 1/24/2008 8:24:48 AM
Author: whitedragon
Lisa,

I''m a bit new here myself, but I believe the HCA measures light return based on angles and table and depth %--whereas ''cut'' as defined on your cert is how well what AGS, GIA, (or whoever else) felt that the diamond cutter did on your stone. As such, you''ll note that on the HCA page is mentioned that it cannot account for symmetry and polish as it has no idea. This being said, your diamond''s actual polish and symmetry are going to tell the real tale.

HCA is just meant to help people weed out potentially poor-performing stones. If you already have yours and it performs well, then I don''t think you quite have much to worry about. : )

Hope this helps a bit?

Whitedragon, I agree with your bottom line. T&CO has graded the actual diamond and its finish so Lisa should absolutely enjoy it.
In my OCD way I’d just note that the HCA is not actually measuring anything. It’s taking an imaginary outline of the diamond and making a prediction based on research. It is a great tool and extremely useful, but it doesn’t ‘see’ the diamond where the other systems do. GIA''s performance grading system is similar to HCA, except it uses more numbers in constructing the diamond’s outline. The AGS system takes a scan of the actual diamond and uses ray-tracing to arrive at light performance values for how all 57 facets interact. Obviously the advantage the labs have is seeing the actual diamond, evaluating durability, finish etc. HCA motors along pretty well considering the diamond could be thousands of miles away!

All of these systems are good: The HCA has a US Patent, the GIA has history and reputability and the AGS system has recently received scientific recognition but they don’t agree 100% (though they all overlap).

 

[lisa1.01fvs1]

John & Whiteflash,

Thanks much, wow for an obsessive-compulsive, overly intense and detail oriented nut, it is a relief to read your words.

So much to know with diamonds.......I took a photo last night and saw what could possibly be "arrows" any thoughts?

I apologize in advance for my amateur photography, knowledge, etc... I probably need an infrared thingy to see the H&A pattern.

--Lisa (having trouble posting pic.

 

[lisa1.01fvs1]

Sorry Whitedragon,

 

[JohnQuixote]

Lisa - glad to help. Yes, the 'arrows' effect can be seen best in diffused light by holding the diamond very still and blocking light coming from the highest angles (directly overhead). The dark areas are literally the shadow created by your head (or the camera) where the light can't reach the lowest parts of the diamonds.

The technical names are obstruction, head shadow or obscuration. In GIA courses they teach that head shadow is "a reflection of you; seen in the diamond."

 

[Garry H (Cut Nut)]

Date: 1/25/2008 2:27:41 PM
Author: JohnQuixote
In GIA courses they teach that head shadow is ''a reflection of you; seen in the diamond.''

Do they really John?
That is exact wording that I used to describe the bow tie effect in marquise for 20 years.
Contrary to something GIA published many years ago describing a nailhead efect in a deep round brilliant as caused by leakage.

Big ships can turn

 

[lisa1.01fvs1]

Ok -- so John & Cut Nut,

I have arrows visible to the eye? What about the Hearts?

Lisa

 

[Shay37]

Date: 1/25/2008 8:27:34 PM
Author: lisa1.01fvs1
Ok -- so John & Cut Nut,

I have arrows visible to the eye? What about the Hearts?

Lisa

What ones you might or might not have are currently upside down.

No worries. Your diamond looks lovely. Please don''t let us nutso number split hairs until they scream people make you equally crazy.

You see the diamond. What does it look like to you? It sure looks pretty in your pic. Enjoy.

shay

 

[Kaleigh]

Enjoy your gorgeous diamond. I think it''s a stunner. Mine is from Tiff''s too, and I adore it.

 

[lisa1.01fvs1]

style="WIDTH: 97.44%; HEIGHT: 213px">Date: 1/25/2008 9:05:01 PM
Author: Shay37

Date: 1/25/2008 8:27:34 PM
Author: lisa1.01fvs1
Ok -- so John & Cut Nut,

I have arrows visible to the eye? What about the Hearts?

Lisa

What ones you might or might not have are currently upside down.

No worries. Your diamond looks lovely. Please don''t let us nutso number split hairs until they scream people make you equally crazy.

You see the diamond. What does it look like to you? It sure looks pretty in your pic. Enjoy.

shay

You and Kaleigh are absolutely right but how can you avoid falling into the "how does my stone stack up" against ALL this info.?

I hate feeling like I didn''t know what I was doing, even though I thought I did, over there in Tiffany land.

All said, it is a gorgeous diamond that I treasure.

--Lisa

 

[Garry H (Cut Nut)]

the star pattern shows good optical symmetry, so the slightly high HCA should not be a problem

enjoy it, and keep it clean
boiling water, ammonia and detergent with a good scrub with tooth brush behind the stone and a good rinse and dry

 

[diamondseeker2006]

Lisa, welcome to PriceScope! Your rings are very beautiful! There are many fans here of the Tiffany solitaire!