“Please tell me the differences between Blue Nile Signature Princess cut diamonds and Brian Gavin Signature Princess cut diamonds, specifically I would like a comparative analysis of this 1.90 carat, G-color, VS-2 clarity, Blue Nile Signature princess cut diamond, and this 1.930 carat, G-color, SI-1 clarity, Brian Gavin Signature princess cut diamond. Please tell me which of the two princess cut diamonds has the best proportions, and which princess cut diamond you would purchase. These seem to be the best ideal princess cut diamonds that I can find which weigh just under the 2.00 carat mark where prices seem to increase substantially.” ~ Thatcher T.
Note that this client ended up purchasing a Brian Gavin Signature Cushion cut diamond after a conversation with his girlfriend about what diamond shape she preferred… So these two diamonds are available!
While I’m certain that both of the diamonds are beautiful, my personal preference is for the 1.931 carat, G-color, SI-1 clarity, Brian Gavin Signature Princess cut diamond because it features a three chevron facet structure on the pavilion side of the diamond. The three chevron facet structure is going to produce sparkle that is larger in size, and which is bolder, brighter, and more vivid, than the smaller sparkle that a four chevron facet structure princess cut diamond will typically exhibit. This is of course largely a matter of personal preference.
The 1.90 carat, G-color, SI-1 clarity, Blue Nile Signature Princess cut diamond features a four chevron facet structure on the lower half of the diamond. I recommend reading about The Effect of Chevron Facets upon Light Performance in Princess Cut Diamonds for additional insight on this subject, however the basic premise is that a higher number of chevron facets results in the light being broken up into smaller and smaller pieces. The challenge with sparkle that is smaller in size is that our human eyes can experience difficulty dispersing the light into the colored flashes of light known as dispersion or fire. Thus princess cut diamonds that feature four or five chevron facets, often appear to exhibit more brilliance (white sparkle) and might seem to be a bit icy in appearance ~ which some people like, however I personally prefer a balance of brilliance and dispersion, and sparkle that is larger in size, and bolder in appearance. One thing that you want to take note of with princess cut diamonds graded by the GIA is that the diamond grading report does not provide the crown height or pavilion depth measurements, which means that you don’t really know how the upper and lower halves of the diamond are divided. Thankfully this information is provided on the supplementary GCAL report.[separator]
In this particular instance, the crown height of the diamond is 10.9% and that is sufficient. The optical brilliance analysis indicates that the diamond is returning a high volume of white light, however it is clear from the image provided, and the clarity image, that the pattern of light return is not evenly distributed throughout the diamond. This however is pretty typical of princess cut diamonds, even those that receive a symmetry grade of GIA Excellent or AGS Ideal-0 because most diamond cutters fail to polish the facets of the diamond so that they are all relatively even and on the same plane.
If we look at the clarity photograph, ASET Scope image, and Ideal Scope image provided for the 1.930 carat, G-color, SI-1 clarity, Brian Gavin Signature princess cut diamond, we can see that the pattern of light is rather evenly distributed throughout the diamond. And the diamond grading report issued by the AGS Laboratory features an ASET image which indicates that the diamond is going to be incredibly bright, but also that the light is evenly distributed. This is represented by the colors red, green, and blue, which represent different intensities of light which were present within the test chamber and the degree of contrast being exhibited by the diamond. This article will further explain what the different colors of an ASET image mean.
Note that the diamond grading report issued by the AGS for princess and other fancy shape diamonds provides complete insight into the proportions of the diamond, it is not necessary to supplement a diamond grading report issued by the AGSL with additional proportions analysis. And the light performance based ASET analysis provides clear insight into how effectively the diamond is making use of the light which is available to it from within the room.[separator]
So it seems to me that the decision to purchase a Brian Gavin Signature Princess cut diamond over a Blue Nile Signature Princess cut diamond, or vice versa, comes down to a matter of whether you think you might prefer sparkle that is larger and bolder in appearance, or smaller and likely to give an icier look. I know that I’m partial to broad spectrum sparkle that is larger in size, but you might prefer sparkle that is smaller in size, both are excellent options.
The reality however is that every diamond should be considered on it’s own merits. Earlier versions of Brian Gavin Signature Princess cut diamonds may have featured a variable number of chevron facets, but his ongoing research into light performance for princess cut diamonds brought him to the conclusion that three chevron facets yields the best overall volume of light return and sparkle.
Since princess cut diamonds can be a bit trickier and involved than rounds, I definitely recommend taking advantage of my free Diamond Concierge Service, and let me take a look at the options available, and provide you with an indication of which diamond I would be inclined to buy personally…
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