Yesterday I wrote about The Last Unicorn, the last Crafted by Infinity Princess Cut Diamond that is available online, it was an exciting discovery because I thought that they were extinct. Since it was a truly rare find, I felt that it was worthy of its very own feature article, but I wanted to mention that I find the light return and visual performance of the Brian Gavin Signature Princess Cut Diamond to be just as impressive. The challenge is that there is only a limited number of them available at the moment because Brian has been so busy cranking up the production of his incredible, new Signature Cushion Cut Diamonds. To be honest, I’m not really sure which one to tell you to purchase…
I ran through the inventory of Brian Gavin Signature Princess Cut Diamonds weighing between 0.70 – 1.10 carats and cherry picked the ones which I feel are really tempting, and am going to evaluate them in order of carat weight, while explaining the methodology behind selecting an AGS Ideal-0 Princess Cut Diamond
Before I do so, let’s get a few things out of the way… Every one of the diamonds listed below is from the Brian Gavin Signature Princess Cut Diamonds collection, which means that they have all been graded by the American Gem Society Laboratory (AGSL) and have an overall cut grade of AGS Ideal-0. This means that every one of them has Zero Ideal Cut Proportions, Ideal Polish, Ideal Symmetry, and they have Ideal Light Performance, as determined using the proprietary Angular Spectrum Evaluation Tool, the results of which are featured in the scan image which appears in the middle of the AGSL Diamond Quality Document. In addition, all of the diamonds have a fluorescence rating of negligible.
Interpreting ASET images for Princess Cut Diamonds:
The American Gem Society Laboratory (AGSL) developed their proprietary Angular Spectrum Evaluation Technology (ASET) to determine how efficiently a diamond is gathering and reflecting back the light which it gathers from its surroundings. A picture of the ASET scan appears in the center region of every Platinum Light Performance diamond grading report issued by the AGSL, and is intended to provide consumers with all of the information that they need to select a high performance diamond without having to become experts in diamond design. The image which appears to the left, is an example of an AGSL Platinum Light Performance diamond grading report, issued for a Brian Gavin Signature Princess Cut diamond. Using the explanation provided below, you will be able to determine where in the room the diamond is gathering light from… it’s pretty cool!
The color red is used to represent light which enters the diamond from 45° up to perpendicular with the table facet, this is the brightest light which makes the diamond brilliant. You want the majority of the diamond which you select to be red…
The color green represents light which is not as bright, it enters the diamond from 45° out to the horizon. It should be noted that it is completely normal for the center region of the table facet to be red, green or a combination thereof because they share the 45° factor.
The color blue represents contrast which is what enables our eyes to see, this is light which could have entered the diamond, but which is being blocked by our heads as we look at the diamond. In the case of these images, the contrast is created by the camera lens which is located above the diamond while it is being photographed.
Black and White represents leakage which is present in all diamonds to some extent, but some diamonds leak light more than others depending on the proportions and precision of optical symmetry. The lighting environment being used at the time the diamond is being photographed will determine whether the leakage appears as black or white.
As you can see from the ASET image for this 0.707 carat, H-color, SI-1 clarity, Brian Gavin Signature Princess Cut Diamond, it is a very bright diamond! All that red which is present throughout the diamond, and which extends outwards into the tips, is going to make sure that your eyes are drawn out to the tips of the diamond, because they are going to be nice and bright! The green sections merely represent light which is being gathered and reflected back by the diamond from 45° out to the horizon, ideally you want to see more red than green. As you can see, this diamond is a nice square looking princess, and the primary inclusions are a couple of small feathers that are of no consequence.
Length to Width Ratios of Princess Cut Diamonds:
I really like the look of this 0.734 carat, H-color, VS-1 clarity, Brian Gavin Signature Princess Cut Diamond which measures 4.96 x 4.92 x 3.65 mm, which results in a length to width ratio of 1.0081:1.00 so it’s nice and square. In case you’re wondering, the way that you determine the length to width ratio of a fancy shape diamond, is to measure the diamond from edge-to-edge as pictured to the left, then divide the longest edge-to-edge measurement (4.96 mm in this case) by the shortest edge-to-edge measurement (4.92 mm in this case) and then compare that to 1.00:1.00 which would be perfectly square, and expressed as a “one to one” ratio.
I mention this because a lot of princess cut diamonds are actually rectangular, with length to width ratios between 1.20:1.00 and 1.30:1.00 which is another thing that sets Brian Gavin’s princess cut diamonds apart from the pack. It should also be noted that we don’t usually run the numbers out as far as I did, they are generally only expressed as far as the second decimal place, but I wanted to provide an example of how it’s done.
All right, so the next diamond we’re going to discuss is this 0.781 carat, F-color, VS-1 clarity, Signature Princess Cut Diamond from Brian Gavin which measures 4.99 x 4.91 x 3.79 millimeters. Using the information provided above, what is the length to width ratio?
If you said 1.02:1.00 you’re correct. And if you just exclaimed “What?!?!” it’s because if you divide 4.99 by 4.91 you get 1.016 and since the digit located in the third decimal place is five or more, we round the number in the second decimal place up… and I didn’t tell you that. Doh!
I just love how icy this 1.063 carat, F-color, VS-1 clarity, Brian Gavin Signature Princess Cut Diamond looks in this photograph! The contrast created by the camera lens being reflected by the pavilion facets reminds me of a kaleidoscope, I’ll bet that this diamond is simply gorgeous when it’s in motion! The F-color is certainly going to help it face up nice and bright, and the ASET image for this diamond looks fantastic.
Feel free to take advantage of my free Diamond Concierge Service if you’d like assistance selecting a princess cut diamond, or if you have any other diamond related questions. The Diamond Concierge Service is absolutely free, my fees are paid for by the vendors who I work with, but I’m happy to look over the details for diamonds that may not be sourced from one of those vendors also! Be sure to provide me with the details of the diamond you are searching for, including the shape, range of carat weight, color, clarity, and price!