HI everyone!
A common question many diamond shoppers have is about "certificates"
If a diamond is "certified" that's a good thing, right?

Today many people -certainly the readers of this forum- are aware that GIA is the best lab.
Still, we find a lot of shoppers who want to "game the system": by buying a "discounted" stone with an EGL report.
Say a diamond graded J/SI1 by GIA is $10,000.
A diamond of similar size and shape graded J/SI1 by EGL might be $7500.

How about an EGL graded H/VS2 for $10,000.
Is that better than the GIA J/SI1?
I mean, who wouldn't rather have a VS than an SI?

The problem is, there's no consistency in how far off the EGL report might be.

To demonstrate this, I'm going to use a stone we were offered by one of our cutters.

I love the stone. it's one of those super charming light browns that is almost "peachy" sometimes.

What did EGL grade this stone?
I color, SI1 clarity.

What is the actual color and clarity of the stone?
Well, at this point, since there is no GIA report, I will need to grade the stone.
I see the stone as an L ( or M) color, I1 clarity.

Let's have a look at the diamond face down on a piece of paper.
From this perspective, the Brown is easy to see.


Clarity: I think it's a great I1- nonetheless, there's enough imperfection to surpass an SI2 IMO

In the shot below you can see the feather at about 2:00
and a second feather at about 7:00.
Then a faint crystal, located pretty much dead center.


If the stone had no other imperfection, I believe GIA would grade the crystal, on it's own, to be a VS2.

Each of the feathers - judged on it's own- would likely get SI2 from GIA.
Put all three together and it's going to get I1 from GIA.
This is a great example of how clarity grading is cumulative.
You might see an I1 that only has one imperfection- but a large one.
In this case there's a greater number of less serious inclusions. The result is a stone which is pretty much eye clean.
But that's really no excuse for grading the diamond SI1!

It's important to note that the EGL that issued this grade is, I believe, a non USA EGL, which are acknowledged to be the worst. Of course once we're allowing for non GIA "certificates", it's a long slippery slope.

The bottom line: Since the diamond sells $26,950 the lack of GIA is not a concern to me, as a wholesale level buyer.
A legit I/SI1 4 carat is going to cost close to $50k

To me, the lack of GIA makes little difference- but I know who cut the stone- and that I can trust them.

To a buyer it makes a huge difference.
Say the stone was represented as an I/SI1.
After all, it's certified, right?
Then one seller is charging $27k for a stone which is -ostensibly- the same grade as the $47K diamond.

To me, the willingness to advertise a stone like this as an I/SI1 indicates a lack of either knowledge of diamonds, or integrity.
Of course it goes on every day.

NOM    me LIKEE!

That is such a spot on question Jen!
The answer is, no, there's no "method to their madness"

I have two stones on my desk- both graded by EGL Belgium.
One is graded K/VS1.
I'd say it's an M.
The other graded H/SI2.
I'd have to say that sucker is a G!
It's also clearly an I1, but I'd say in this particular case EGL was too tough on the color!

I really love the question because it's a common thought and a big part of this problem.
If it were possible to accurately calculate how far off EGL is, then the reports would have value as a grading tool.
They simply don't have the consistency........

The likelihood of the grade being wrong in your favor is minuscule- that's an oddity.
but I suppose it's part of the definition of "inconsistent"

Here's the 1.02 graded K by EGL.
In this photo it looks fairly white- bu it's the fluorescence doing that.....


Now look at it in light that has a smaller UV content.....

Great question Jen- who knows?

One theory: Companies that give a lot of business to EGL get better grades.
Another line of thinking is that by using such soft grading EGL might gain business- in other words, the cutters know their L color is going to get an I or J, so they simply skip GIA and go for EGl...

Without a doubt there are scads of sellers that realize the grading is soft, yet advertise the EGL grades....

I'd say it's rare that a stone would be graded a higher color by the non GIA labs.

I keep looking at it and thinking..."Peach"

Very light pinkish brown?

It does look a little peachy. It's a beautiful stone and it would be perfect set as an enhancer to a longer length riviera necklace. That would be pretty much my ultimate jewelry piece.

Jen

It's a lovely cut. That's how it looks to me anyhow. And it's BIG. HUGE. A monster.

Now, THAT is a funny statement! Talk about the pot calling the kettle black... a-hem. 

(referring to Miss Mikla's most recent ginormous custom ring, of course)

I like small diamonds, too; like pretty little blue ones in pink tutus with side moons. 

But I'd love to get this one as an enhancer for my pearls, especially since I'm thinking Champagne color gown when we finally do the wedding.  (Yeah, Dream on.  Like that could ever happen when I want a house.)