"I'm trying to decide between several James Allen True Heats and GIA Excellent cut diamonds. Having read several of your diamond buying tutorials, I've decided I want a diamond with Tolkowsky proportions.
My girlfriend loves the Octagon Halo setting by James Allen. I found several diamonds on James Allen that seem to meet your selection criteria. Now I need your help deciding which of the diamonds offers the best light return.
I know that you prefer James Allen True Hearts diamonds, but I'm wondering whether the difference between those and one of these GIA Excellent cut diamonds will be noticeable to somebody like me."
"I hope that it's not too much to ask, but I've narrowed it down to nine diamonds. Five James Allen True Hearts diamonds and four GIA Excellent cut diamonds. Would you mind looking over the details and helping me choose the best one? I'm also wondering about your thoughts about how James Allen True Hearts diamonds compare to other brands?"
Riddle me this. Which diamond looks better to you? The James Allen True Hearts Diamond on the left or the GIA Excellent cut diamond on the right? Here are the details:
Both diamonds have a 40.8 degree pavilion angle which should produce a high volume of light return. The crown angle measurement is 34.5 degrees for both diamonds. And the lower girdle facet length is stated as being 75% although the GIA rounds these measurements off so there are likely to be slight differences.
Setting those facts aside for a moment, just look at the two diamonds and tell me which one looks better to you? Don't get too caught up in the difference in brightness since that is likely to be due to a difference in calibration in the imaging systems used to capture the images.
What I want you to look at instead is the degree of contrast brilliance and how evenly light appears to be reflecting throughout the body of the diamonds. Which diamond looks crisper to you? Which diamond seems to exhibit better optical precision? Which diamond seems to be brighter and have less obstruction under the table facet?
I'll give you a hint. The James Allen True Hearts diamond on the left. Notice how the triangular sections under the table facet of the GIA Excellent cut diamond on the right don't look as bright as the James Allen True Hearts diamond on the left. The difference between the two diamonds is most likely just a matter of optical precision. Which is the consistency of facet size, shape, and alignment as the facets are polished on to the surface of the diamond.
Now that you know that James Allen True Hearts diamonds are cut to exhibit a higher degree of optical precision than most GIA Excellent cut diamonds, it's time to review each of the diamonds individually. This 1.01 carat, G-color, VS-1 clarity, James Allen True Hearts diamond is graded on the AGS Light Performance grading platform, however the diamond grading report does not provide an ASET image.
The ASET image provided on the Platinum Light Performance report would enable us to determine how evenly the diamond is reflecting light and where in the room it is gathering light from.
I have to admit that this is a pet peeve of mine. The cost of the Platinum Light Performance report that contains the ASET image is just a little more expensive than the basic report format seen here.
James Allen does provide this Ideal Scope image of the diamond, which looks great! Notice how consistent the distribution of color is across the table facet. Based on this Ideal Scope image it is safe to assume that the diamond is not leaking any substantial amount of light.
With this in mind, you might wonder whether an ASET Scope image is necessary. I suppose it depends on the degree of information necessary for you to be comfortable with your decision. An Ideal Scope is designed to help you identify light leakage within a diamond. An ASET Scope is intended to demonstrate where in the room the diamond is gathering light from and show you how evenly light is reflecting throughout the diamond.
From my perspective, I like to have as much information as possible to help me make an informed decision. Thus, I prefer diamonds graded on the AGS Platinum Light Performance grading platform because I want the insight provided by the ASET Scope image.
The proportions of this 1.01 carat, G-color, VS-1 clarity, James Allen True Hearts diamond do meet my selection criteria. The 40.7 degree pavilion angle should produce a high volume of light return. The 34.7 degree crown angle should produce a virtual balance of brilliance and dispersion.
The combination of the higher degree of optical precision that creates the hearts pattern and the 76% lower girdle facet length should produce broad-spectrum sparkle. That is sparkle which tends to be larger in size and bolder, brighter, and more vivid than what standard ideal cut diamonds exhibit. The hearts pattern is pretty consistent in size and shape. However, if you look closely at the tip of the heart in the five o'clock position you will see that it is twisting slightly.
Twisting in the tips of the hearts indicates that there might be a difference in the length of the lower girdle facets. It could also be due to the alignment of the camera being slightly off kilter from the surface of the diamond. Obviously, I tend to look for hearts and arrows diamonds that exhibit the most precise patterns possible. Of course, you're never going to find a perfect pattern of hearts and arrows because these diamonds are turned on the wheel by hand.
This is the 1.05 carat, G-color, VS-1 clarity, James Allen True Hearts diamond pictured on the left side of the feature image for this article. The hearts pattern looks pretty good to me with only very minor variances. Take a look at the heart in the six o'clock position and then across at the diamond in the twelve o'clock region. Then go back to six o'clock and allow your eyes to wander around the hearts in the clockwise direction.
Look closely at the tips of the hearts, I'm not seeing any twisting. There are some small splits in the clefts of some of the hearts. The Ideal Scope image looks pretty good, but the distribution of light appears to be more even on the 1.01 carat, G-color, VS-1 clarity, James Allen True Hearts diamond discussed previously.
This diamond has a pavilion angle of 40.8 degrees and should exhibit a high volume of light return. The 34.5 degree crown angle should produce a virtual balance of brilliance and dispersion. The higher degree of optical precision and 75% lower girdle facet length should produce broad-spectrum sparkle.
This 1.08 carat, G-color, VS-1 clarity, James Allen True Hearts diamond is graded on the Platinum Light Performance grading platform. This means that we have an ASET Scope image that will enable us to determine how evenly light is reflecting throughout the diamond.
The ASET Scope image is the multi-colored picture that you see in the middle of the diamond quality document to the left. All of that red indicates that this diamond is gathering light from all the right places and will look super bright!
Pay particular attention to how evenly the colors are reflecting throughout the diamond, this is an indication of a higher degree of optical precision. However, the ASET Scope image is not a good way to judge optical precision, we'll use a hearts and arrows scope to get a really good look at the hearts.
The hearts pattern exhibited by this 1.08 carat, G-color, VS-1 clarity, James Allen True Hearts diamond looks pretty good! The hearts have a nice shape to them and I'm not seeing a lo of twisting in the tips. There is a slight difference in size (look at the heart in the 7 o'clock position and then across to the heart in the eleven o'clock position) but it's something you're going to have to look pretty hard to see.
Honestly, I'm more concerned about whether the shape of the hearts is consistent and whether there is twisting in the tips because that is an indication that there might be a difference in the length of the lower girdle facets and this might just be a matter of camera tilt or the alignment of the diamond upon the platform. The diamond also looks really good in the Ideal Scope image.
By all indications, this James Allen True Hearts diamond should deliver a high volume of light return and a virtual balance of brilliance and dispersion in the form of broad-spectrum sparkle.
This 1.15 carat, G-color, VS-1 clarity, James Allen True Hearts diamond looks good by the numbers. It should exhibit a high volume of light return and a virtual balance of brilliance and dispersion.
There is a bit more fluctuation than I like to see in the size and shape of the hearts. However, I'm more concerned about what may or might not be a cloud that is visible along the upper edge of the table facet. The diamond grading report does not indicate a cloud, but this sure looks like a cloud to me.
If you left click your mouse over the video and hold it down while dragging the diamond left and right you'll see what I mean.
The cloud appears not to be on the surface of the diamond, but seems to extend down into the diamond. Which leads me to believe that it is an undocumented cloud of pinpoint size diamond crystals. A cloud this extensive is likely to interfere with the volume of light return. While small clouds of pinpoint size diamond crystals tend to be of no consequence and just look like a cluster of sparkling dust when viewed under magnification.
The diamond grading report indicates that the primary inclusions are a feather and some pinpoint size diamond crystals. There is no mention of a cloud and the comment "additional clouds are not shown" is not present on the report.
It is possible that this is nothing more than a fingerprint, but it sure does look like a cloud of pinpoint size diamond crystals to me. In which case, the diamond grader might have missed something. Hey, we're all human, right? But if that's the case, this diamond might be more of a VS-2 than a VS-1 and we should ask the Gemologist at James Allen to examine this diamond further before you buy it.
Since this 1.18 carat, G-color, VS-1 clarity, James Allen True Hearts diamond is graded by the GIA with an overall cut grade of GIA Excellent, it is both a James Allen True Hearts diamond and a GIA Excellent cut diamond.
If you look closely at the tip of the heart in the relative seven o'clock position you will see that it is bending to the left, while the tip of the heart in the six o'clock position is bending to the right. That's a bit of an issue from my perspective and is a good indication that there is probably something off kilter in the optical precision part of the equation. The odds are that there is a difference in the length of the lower girdle facets and this is affecting the length of the reflections that create the hearts patterns.
The slight bend in the tips of the hearts is an indicator of optical precision, but it not the reason why I would reject this diamond automatically without a second glance.
The reason why I would reject this James Allen True Hearts diamond is because it contains a cavity. A cavity in a diamond is similar to a cavity in a tooth or other object. It's a hole in the surface of the diamond and in this case, it's located in the crown facets on top of the diamond. The problem with cavities is that they are prone to filling up with dirt and grime. When this cavity fills up with dirt, it's going to look like a big, black spot on the top of the diamond, which kind of defeats the purpose of the VS-1 clarity grade.
In addition, a cavity in the surface of a diamond might pose a durability risk to the crystal structure. While we're on the subject, I automatically reject any diamond that contains a cavity, chip, etch channel, knot, or laser drill hole because these types of inclusions might weaken the crystal structure.
At this point, we've taken an in-depth look at the James Allen True Hearts Diamonds you are considering. Now, we're going to look at the characteristics of the GIA Excellent cut diamonds in the same detail to see whether any of them hold a candle to the hearts and arrows cut diamonds on your list.
The first thing I noticed about this 1.00 carat, G-color, VS-1 clarity, GIA Excellent cut round diamond from James Allen is the moderate amount of obstruction that is visible between the arrows pattern. Just to make sure that we're on the same page, I'm referring to the black asymmetrical shapes located along the edge of the arrows.
Obstruction is created by a combination of proportions and lower degrees of optical precision. It is not the same as "clustering" which is contrast that appears at the base of the arrows pattern.
Obstruction often shows up as light leakage in ASET Scope and Ideal Scope images and can make the mid-section of a diamond look dark.
Unfortunately, the supplier for this diamond does not provide ASET or Ideal Scope images within the listing details. Thus, we have no way of accurately assessing the degree of optical precision or the degree of light leakage. However, it is safe to assume that if the diamond exhibited a crisp and complete pattern of hearts and arrows, then James Allen would place it within the inventory of the James Allen True Hearts collection.
The second thing I noticed about this diamond is that it exhibits a thinner looking arrows pattern than the James Allen True Hearts diamonds that you are considering. This is because this diamond has lower girdle facets in the range of 80% which tends to produce thinner looking arrows.
It is important to note that the GIA rounds the lower girdle facet length off to the nearest five percent. Thus, a diamond with 80% lower girdle facets stated on the diamond grading report might exhibit broader arrows if the actual length is closer to seventy eight percent.
At the same time, the diamond has a pavilion angle of 40.8 degrees and should exhibit a high volume of light return. The 34.5 degree crown angle should produce a high volume of light return. The combination of the proportions and overall cut rating put this diamond in the Top 1% of the annual production for rounds. Thus, it's simply a matter of deciding what level of optical precision and sparkle factor appeals to your preferences and budget.
This 1.00 carat, G-color, VS-1 clarity, GIA Excellent cut round diamond from James Allen is not exhibiting obstruction under the table facet like the diamond above. However, I am seeing a bit of a paddle effect around the tips of the arrows.
The paddle effect exhibited by this diamond becomes more apparent when I move the diamond left and right. The downside of this optical effect is that I think it makes the kite shaped bezel facets of the diamond look dark.
The proportions of the diamond are within my preferred range and thus it should have good light return and sparkle factor.
All right, I want to point out that the paddle effect exhibited by this diamond might simply be a matter of the camera being too close to the surface of the diamond. However, the paddle effect that we're seeing in this diamond might also be due to the proportions or the degree of optical precision.
This is where it would be helpful to have ASET and Ideal Scope images, but the supplier for this diamond doesn't provide them. Obviously, James Allen doesn't think the diamond is hearts and arrows, or it would be placed in the James Allen True Hearts collection. One of the issues I have with the GIA Laboratory is that they round off a lot of the measurements after taking the average of eight measurements per section, the AGS doesn't do that.
The total depth of this diamond is stated as being 61.5% but by my calculations it should be 61.6%. How did I figure that out? It's easy, just take the average outside diameter of the diamond and divide the depth by that measurement. In this instance, the diamond measures 6.43 - 6.47 x 3.97 mm. You would calculate the total depth measurement like this:
6.43 + 6.47 = 12.9 / 2 = 6.45. Divide the depth 3.97 / 6.45 = 0.6155 which should be rounded up to 61.6% total depth. Now, what if the crown angle of 34.5 degrees is more like 34.8 degrees? And what if the pavilion angle measurement is off a little bit? A little wiggle here, a little wiggle there, and we just might have the reason why this GIA Excellent cut diamond is exhibiting such a pronounced paddle effect.
Or perhaps, all of this is being caused by the camera lens being too close to the surface of the diamond. The fact of the matter is that as a diamond buyer, I'm not going to worry about it. I'm more likely to pass on this sucker and opt for a diamond that isn't exhibiting these optical defects that cause me to stop and ponder such things.
This 1.01 carat, G-color, VS-1 clarity, AGS Ideal-0 cut diamond from James Allen is graded by the American Gem Society. The diamond received an overall cut grade of AGS Ideal-0 on the Light Performance grading platform, but the report does not provide an ASET Scope image.
While this is a good start, I like to have the insight provided by ASET and other reflector scope images when I set out to buy a diamond.
Call me paranoid, but when a supplier submits a diamond to the AGS for grading and doesn't spend the few dollars extra for the Platinum Light Performance report, it always makes me wonder why they wouldn't elect to pay for the report that provides greater detail.
Unfortunately, the most likely answer is that the supplier is being cheap. Despite the fact that the paranoid side of my persona would like to believe that they're trying to hide something, the reality is that a few dollars saved on each report adds up to hundreds of thousands of dollars at the supplier level.
This 1.01 carat, G-color, VS-1 clarity, AGS Ideal-0 cut diamond from James Allen looks promising by the numbers. The 40.8 degree pavilion angle should produce a high volume of light return. The 34.3 degree crown angle should produce a virtual balance of brilliance and dispersion. The 76% lower girdle facets are producing an arrows pattern that looks nice and balanced.
As you can see, the diamond is exhibiting strong contrast brilliance and there is not a lot of obstruction between the arrows. It would be interesting to see ASET Scope, H&A Scope, and Ideal Scope images for this diamond to be able to judge the degree of optical precision. While it's unlikely to be cut to the higher degree of optical precision required for hearts and arrows, it seems to be a very nice ideal cut.
This 1.05 carat, G-color, VS-1 clarity, GIA Excellent cut round diamond from James Allen has a pavilion angle of 40.8 degrees and should exhibit a high volume of light return. The 34.5 degree crown angle should produced a virtual balance of brilliance and dispersion. The 75% lower girdle facet length is producing a nice arrows pattern and the diamond exhibits great contrast brilliance.
You might have noticed that I've posted a different photograph than the one usually provided by James Allen. This is a screenshot of the Segoma Imaging file available for this diamond within the multiple listing service that we use to trade diamonds globally. As you can see, an Ideal Scope image is available for this diamond. Unfortunately, the file was 404 not found when I clicked the icon.
If you've read my James Allen Diamonds Review then you know that both James Allen and Segoma are owned by R2NET. Did a lightbulb just turn on inside your head? "Oh, so that's how James Allen is able to provide high definition video and images for all those virtual diamonds!"
If you've been paying attention, then I'm sure you realize that James Allen True Hearts diamonds are worth the premium. The higher degree of optical precision that creates the hearts and arrows pattern produces a higher number of virtual facets. Those internal reflections of light will create more sparkle and sparkle which is more vivid and intense than standard ideal cut diamonds tend to produce.
The reason why James Allen True Hearts cost more than standard GIA Excellent cut diamonds is because it takes longer to polish diamonds to reflect the higher degree of optical precision. Cutting diamonds to hearts and arrows specifications also requires greater talent and more expensive equipment.
At the same time, you can also see that there are variances in the degree of precision exhibited by the hearts patterns of James Allen True Hearts diamonds. Thus, you'll want to pay particular attention to the consistency of the hearts when deciding which James Allen True Hearts diamond to purchase.
Hearts & Arrows diamonds offer the highest degree of light return and sparkle which is more vivid and intense than standard ideal cut diamonds. Unfortunately, the gemological laboratories do not account for optical precision when grading diamonds for cut quality. Thus, you will see a broad range of inconsistency in the hearts and arrows patterns of diamonds purported to be hearts and arrows.
It is important to realize that it is unlikely you will ever see a perfect pattern of hearts and arrows because these diamonds are turned on the wheel by hand. Thus, there are always going to be minor variances in the size and shape of the hearts. At the same time, this means that some hearts and arrows diamonds will exhibit more precise patterns than others.
This statement applies to James Allen True Hearts diamonds and other brands, such as:
With that in mind, I tend to search all of these vendors to determine who has the best options available within the range of characteristics and price you are considering. Keep the diamonds which are of interest to you open in separate tabs in your browser and then determine which ones offer the highest degree of optical precision.
Obviously, I realize that you're looking for one carat, G-color, VS-1 clarity, ideal cut diamonds. However, I don't know the price range you are working with, so I'll hold off on making additional recommendations at this time.
Feel free to send me links for any diamonds which you are considering. You can paste them into the Diamond Concierge Service form. We will look over the diamond details and provide you with an in-depth evaluation for free. All we ask is that you use the affiliate links provided if you purchase the diamond online.
We also appreciate it immensely if you mention that you are working with Todd Gray and Nice Ice whenever you correspond with any vendor. Not only does it let them know that you are more knowledgable about diamonds than the average consumer, it keeps us in the forefront of their minds.
We're happy to help you evaluate any diamonds you are considering, regardless of whether they are from one of our preferred vendors or another source. Just send us the diamond grading report number and specify whether the diamond is graded by the AGS, GIA, or another laboratory.
We'll look the diamond up by diamond grading report number and provide you with any images that might be available in the multiple listing services (MLS) that we use to trade diamonds globally. Images are currently available for about half of the diamonds listed in the MLS and more and more suppliers sign-up to work with Segoma every day.
Todd Gray is a professional diamond buyer with 30+ years of trade experience. He loves to teach people how to buy diamonds that exhibit incredible light performance! In addition to writing for Nice Ice, Todd "ghost writes" blogs and educational content for other diamond sites. When Todd isn't chained to a desk, or consulting for the trade, he enjoys Freediving! (that's like scuba diving, but without air tanks)