How to evaluate emerald cut on pictures

[PierreBear]

Hi PS Friends,

I understand that you can view stats on a diamond and make sure it fits the general guidelines. I've been reading though that emerald cuts don't necessarily have as strict standards as compared to a round brilliants. So do most people rely on pictures? If so, I'm a bit overwhelmed with how you select emerald cuts based on videos etc. For instance, why in the picture is the one on the left show more darker spots than the one on the right. Do those darker spots indicate light leakage?

Also, are there PS vendors that focuses more on emeralds than others? Just still learning and dreaming. Thanks in advance!

 

[Gypsy]

"Select" is a very ambitious word.

You can't really "select" an EC from just a picture. Or from one of those JA videos where the diamond is sitting on it's side.

Step cuts are difficult creatures.

The best you can do is familiarize yourself with the photo set ups of the different vendors enough that you can eliminate ones with obvious flaws. Then narrow down the choices to ones that lack those obvious flaws, and then request an ASET to show you how the facets are reflecting light and what flaws might be present (like a P3 issue).

And then from there... you probably have to start all over again.

Step cuts are hard.

Honestly, I've had better luck with Enchanted Diamonds on Step Cuts in terms of drop shippers, than JA. The stones resting on their sides like that makes it pretty darned hard to pick immediate winners.

With you need, ideally is a picture a video AND an ASET (plus a good gemologist to review it if you can get one).

That's your 'selection' criteria. The rest is just elimination methods to rule out undesirable traits.

Both of those stones you took a snap shot of have issues. The one the right has all those black facets. That's generally bad because those facets are relatively dead-- that's probably obstruction. And the one on the right has a lot of grey and indistinct facets which can ASET out poorly-- showing leakage. Neither is a good thing.

 

[Gypsy]

Here's my EC/Fancy spiel:

The entire purpose of faceting a diamond is to reflect light.
How well or how poorly a diamond does this determines how beautiful it is.
How well a diamond performs is determined by the angles and cutting. This is why we say cut is king. With fancies though (anything other than a round brilliant), that is a little complicated. But no other factor: not color, not clarity has as much of an impact on the appearance of a diamond as its cut. With fancies "cut" refers to the faceting pattern and the light performance of the stone.

There really is no other way to determine if you have a good fancy is to see images of the stones, and then you need is a way to check actual light performance of your actual stone.

That's what an ASET image does. http://www.highperformancediamonds.com/index.php?page=education-performance Please read.
And ASET shows you how and wear your diamond is reflecting light, how well it is going at it, and where you are losing light return That is why you won't see us recommending vendors like Blue Nile, as they do not provide images or ASET images for their diamonds.

But even an ASET is not, ideally, in and of itself enough to make a selection of a fancy. You want still images. And you want a video.

Why? Well a still is like a nice close up of someone's face. You want to see the stone over all, in terms of shape, the crown and the pattern of the facets and the overall "look" of the stone. A nice video can substitute for that of course. But not all vendors have really good videos. And the more images you get of a stone, the better, honestly.

The video shows you how and where the stone is playing with the available light. It will show you how the stone lights up and dances, and since it's never still on your hand it's important to see the stone in motion if you can. That said with step cuts you have to be very careful of videos were the stone is lying on it's side (like the JA videos). Those are deceptive with step cuts and are NEVER enough to make a decision of selection for a step cut (whereas they can be for cushions, for example), you absolutely need an ASET in combination with of of those videos. If you can't get one for that stone, either have the stone called in for a vendor that will get you one like IDJ, GOG, or BGD, or WF or move on.

And the ASET, well, that's explained above.

 

[PierreBear]

Thanks, Gypsy! It is very evident that you are so knowledgeable. Since it is challenging to gauge a high performing step cut, are there any vendors that specialize more in it than others so you don't have to worry so much about picking the wrong type? I'm only familiar with BGD and WF so far and they don't seem to have videos. Whereas, James Allen has the videos but as you said, you still need to request the ASET.

I'm in dream mode (10 years down the road possibly) when I say this but would like to be educated... if you were planning on getting a large emerald set by Steven K, then would you just allow him to source it as I'm sure he would pick a good stone. However, you might be paying a premium but hopefully not too much but worth it to not pick a low performing one on your own?

Thanks in advance!

 

[two_little_birds]

Good Old Gold is your best bet for emerald cuts. Check-out their emerald cut videos on youtube.