GIA to grade Labs Pass /Fail... 4 C's for Naturals only.

[Rockdiamond]

Again, just my experience

And thank you for sharing!!
Of course there are a lot of other possible reasons.
A lot of natural diamonds can look grey or dull in rings on peoples fingers…. Even wealth folks diamonds get dirty… hahah

Or- they could easily have been clean, yet dull grey natural stones.
I’ve only been to Italy once. I adored it!

Just didn’t see a lot of stones ( especially larger than 1ct) in stores or like what we see on people in the states.

Bottom line is (again) it’s not possible to conclusively know if a diamond was mined or man made without very expensive equipment.
Garry has said that if he sees a piece with no fluorescent diamonds, he’s sure it’s lab grown. I wouldn’t go that far. But of course he’s not saying he can spot labs based on normal appearance.

 

[Texas Leaguer]

It’s my understanding that if an examines a diamond through a loupe and there are no inclusions, jeweler would generally assume it is a lab-grown diamond. I am no expert whatsoever, but my guess is that since a, say, D color 1.5-2-carat diamond with excellent quality and AGS triple zero or close to it would cost probably a minimum of $40,000, and most average folk are not walking around with $40,000 diamonds on their finger, a jeweler would assume a stone with those qualities was created in a lab. Sounds logical to me.

A jeweler has to assume practically every diamond is lab grown today. But with a loupe the large majority of them can be identified quickly by simply reading the inscription. (A natural diamond will not feature a lab grown inscription!)

Stones without inscription, or with inscription covered - say in a bezel, can be identified by other means, including by observing their inclusions, fluorescence, and using a modern diamond testing device (combinations of tests are more definitive).

In some cases where the stone is clean and colorless and type 2 with no inscription indicating lab grown, the stone may be referred to a gemological laboratory for final determination.

 

[Rockdiamond]

A jeweler has to assume practically every diamond is lab grown today

Bingo!!
If it doesn’t have a GIA report and I know and can verify the source….. I assume lab.

 

[AllAboardTheBlingTrain]

A jeweler has to assume practically every diamond is lab grown today. But with a loupe the large majority of them can be identified quickly by simply reading the inscription. (A natural diamond will not feature a lab grown inscription!)

Stones without inscription, or with inscription covered - say in a bezel, can be identified by other means, including by observing their inclusions, fluorescence, and using a modern diamond testing device (combinations of tests are more definitive).

In some cases where the stone is clean and colorless and type 2 with no inscription indicating lab grown, the stone may be referred to a gemological laboratory for final determination.

Could you explain a bit more what you mean about observing inclusions to determine if a diamond is lab or natural? As in, does that mean that they have different types of inclusions?

 

[purplesilk]

Could you explain a bit more what you mean about observing inclusions to determine if a diamond is lab or natural? As in, does that mean that they have different types of inclusions?

Very interesting article by our beloved brilliant John Pollard

Inclusions Seen in Lab Grown Diamonds

There are two ways of producing lab-grown diamonds. These different approaches produce inclusions which differ from those in natural diamonds.

www.igi.org

 

[Texas Leaguer]

Could you explain a bit more what you mean about observing inclusions to determine if a diamond is lab or natural? As in, does that mean that they have different types of inclusions?

Yes, they often have discernible inclusions that are indicative of natural or lab grown. For example, lab grown may have inclusions of the metalic flux that is used in the growth chamber. You see on many reports the term "growth remnant" which is a general term for an inclusion that does not occur in natural diamonds. And there are certain types of crystal inclusions in natural diamonds that would never occur in lab grown.

Having said that, determining the identity of inclusions does take training and experience. So not every jeweler should make conclusive ID on the basis of inclusions alone. There can be some ambiguous types that can potentially be misidentified.

 

[AllAboardTheBlingTrain]

The issue with this is that we have no context. When you say they looked “off”… what specifically was the issue?
Were the stones loose or set?
Were the stones being shown by a seller?
When was this?
It’s getting harder and harder to find funky colored labs as the overall general quality has improved. Also- remember I’ve seen all sorts of funky natural diamonds as well over the years.
Bottom line - it’s not possible to conclusively tell without expensive testing equipment. Not possible by eye. Period.

The three times I’ve seen lab diamonds (that I knew were definitively labs):

1) loose lab growns, G and/or H colour grade (IGI cert), 2ct size. I was looking for stones for studs. They had a weird steely grey colour that was subtle and unmistakable. I saw them in multiple lighting conditions. I also saw some higher colour ones that I wouldn’t have been able to tell the difference, though. This was around a year or year and a half ago, maybe? I remember I posted when I saw them.

2) lab growns set in studs, again 2ct size. They looked kind of dull but not like how unclean diamonds look dull. Again had a weird colour to them - not grey but more blue I guess? Like just a tiny hint of blue. Also at a different lab grown vendor, I saw these only in the store under the jeweller lights as I wasn’t allowed to take them anywhere. Around the same time as the first instance.

3) met someone who was wearing a pair of studs that looked off to me. This is the one where I can’t explain what I mean by off. I just mean that the sparkle wasn’t right, like there wasn’t enough depth to the sparkle. Maybe it was just badly cut, but I’ve never seen that before on anyone. She candidly told me she was wearing labs in her ears and wrist (she was wearing a tennis bracelet) without my asking. I thought the tennis bracelet was indistinguishable but the earrings had seemed off to me.

I’m caveat-ing this by saying I’ve likely seen a bunch of labs that I couldn’t differentiate from natural and therefore it’s not like I have a superpower, but I also do think that the crappy ones do look off and you can tell by looking. Maybe naturals with the same effects also do exist but since I’ve never seen them before and have seen labs like that, I attribute that characteristic to labs?

 

[AllAboardTheBlingTrain]

Yes, they often have discernible inclusions that are indicative of natural or lab grown. For example, lab grown may have inclusions of the metalic flux that is used in the growth chamber. You see on many reports the term "growth remnant" which is a general term for an inclusion that does not occur in natural diamonds. And there are certain types of crystal inclusions in natural diamonds that would never occur in lab grown.

Having said that, determining the identity of inclusions does take training and experience. So not every jeweler should make conclusive ID on the basis of inclusions alone. There can be some ambiguous types that can potentially be misidentified.

This makes a lot of sense. Thank you for answering my question!

Very interesting article by our beloved brilliant John Pollard

Inclusions Seen in Lab Grown Diamonds

There are two ways of producing lab-grown diamonds. These different approaches produce inclusions which differ from those in natural diamonds.

www.igi.org

Super interesting read!

 

[Rockdiamond]

Excellent article by Sir John!!

Having said that, determining the identity of inclusions does take training and experience.

From my perspective, having worked with imperfect diamonds for much of my career:
Based on the photos, none of the imperfections John points out is impossible in a natural diamond.
I've seen everything over the years...diamonds with garnets inside.
Now that might convince me a stone was natural. But I still would not stake my reputation on it.
As someone in the business, I think it's incumbent upon me to ensure I can back up my statements to clients.
For consumers, if you think you can spot lab diamonds, have at it!
Due to the price, it's far more crucial to identify a mined diamond as such, as opposed to lab.
At this point, I consider everything to be lab, unless I know from whence it came.
I advise consumers likewise.

 

[DejaWiz]

Excellent article by Sir John!!


From my perspective, having worked with imperfect diamonds for much of my career:
Based on the photos, none of the imperfections John points out is impossible in a natural diamond.
I've seen everything over the years...diamonds with garnets inside.
Now that might convince me a stone was natural. But I still would not stake my reputation on it.
As someone in the business, I think it's incumbent upon me to ensure I can back up my statements to clients.
For consumers, if you think you can spot lab diamonds, have at it!
Due to the price, it's far more crucial to identify a mined diamond as such, as opposed to lab.
At this point, I consider everything to be lab, unless I know from whence it came.
I advise consumers likewise.

Great advice, David - and I would take it a step further...

Regardless of whether it's a lab grown or natural made diamond, know whence it came because a diamond of either origin can be extremely great quality, extremely bad quality, or anywhere in between.

 

[kenny]

The idiocy of GIA's anti-consumer choices, especially now that they could fully implement the far superior AGS cut grading system full-swing and create a true industry benchmark for the entire globe, never ceases to amaze me...

I agree that AGS's system is superior to GIA's if the goal is the final customers getting diamonds with the best light performance.

But ... "Far superior" for whom?
GIA's bottom line?
Or diamonds' final customers, as in you and I? ... whom BTW are not GIA's customers.
Rather, we are the ultimate customer's of GIA's direct customers, the companies who pay GIA to grade their diamonds.

Even a (so-called) non-profit shouldn't bite the hand that directly feeds it.

 

[oldminer]

The GIA Lab is a for profit enterprise. The GIA is otherwise a Non-Profit entity, but not the Lab.

 

[Texas Leaguer]

I agree that AGS's system is superior to GIA's if the goal is the final customers getting diamonds with the best light performance.

But ... "Far superior" for whom?
GIA's bottom line?
Or diamonds' final customers, as in you and I? ... whom BTW are not GIA's customers.
Rather, we are the ultimate customer's of GIA's direct customers, the companies who pay GIA to grade their diamonds.

Even a (so-called) non-profit shouldn't bite the hand that directly feeds it.

It's true that although GIA's mission is CONSUMER education and protection, the lab's paying customers are for the most part trade members, in particular diamond manufacturers. So there is some inherent conflict of interest.

I do believe GIA seeks above all else to be true to their mission. So they have to take a "first, do no harm" approach to any changes to their status quo. And at times they seem paralyzed by trying to balance the priorities of a wide-ranging global network of clients. Their due dilligence process takes a lot longer than other labs catering to smaller or less diverse constituencies.

They are like an aircraft carrier that likes to travel in a straight line, and is not great at making quick manuevers!