The Effect of Chevron Facets on Princess Cut Diamond Light Performance

Let’s begin with the understanding that Light Performance is a relatively new concept in diamond cutting. The majority of diamond shapes and different cuts were developed before light performance was a factor. Most of the attention regarding improving diamond cut quality, facet design and structure to improve light performance, has been directed towards the development of round brilliant ideal cut diamonds. Brian Gavin is one of the few diamond cutters who is intent on improving the light performance of princess cut diamonds.

How to count chevron facets on princess cut diamond:

Number of chevron facets on a princess cut diamond, courtesy of Brian GavinThe chevron facets polished on to the pavilion section of a princess cut diamond plays a critical role in light performance. This diagram featured in a blog post by Brian Gavin on how to count the number of chevron facets on a princess cut diamond highlights the pavilion facets. The orange colored ‘X’ in the middle is the pavilion main facet. The yellow sections represent the first row of chevron facets. Green represents the second row of chevron facets. Blue represents the third row of chevron facets. Purple represents the fourth row of chevron facets. Each row of chevron facets extends outwards from the pavilion main facet that is located in the middle of the pavilion section. More chevron facets translates to sparkle that is smaller in size. The problem with smaller sparkle is that it is difficult for our eyes to disperse into colored light, thus the diamonds are likely to appear to be more brilliant than exhibit a virtual balance of brilliance and dispersion. They’re also likely to exhibit that crushed ice appearance.

Two chevron princess cut diamonds:

Princess cut diamonds that feature two chevron facets tend to produce sparkle that is larger in size. This might sound pretty good, but I also find that they look kind of bland and watery. From my perspective, two chevron princess cut diamonds shimmer like the surface of a shallow pool or pond. They shimmer a bit and look very bright, but there is not really much going on in terms of sparkle. This is because the virtual facets of the diamond are too large, thus there is not enough scintillation for my tastes.

By the way in the industry, we refer to princess cut diamonds that feature two chevron facets and the pavilion facet as a 2+1. Some people mistake diamonds cut with a pavilion facet and two chevron facets for a three chevron facet diamond, because they count three facet sections on the underside of the diamond. They’re adding up the 2+1, but it is actually one pavilion main ‘X’ pattern, accentuated by two chevron facets on each of the four sides.

Four chevron princess cut diamonds:

A four chevron facet princess cut diamond, would then be referred to as 4+1. What tends to happen here is that the pavilion mains ‘X’ pattern become more elongated and thinner in appearance. This cuts down on the contrast brilliance exhibited by the diamond. It also reduces the size of the virtual facets, which are the internal reflections of light created by the overlapping of facets. Virtual facets are kind of like the reflections created on the fly when you look through a kaleidoscope.

When the light is broken up into smaller and smaller pieces, the reflections of light then become smaller. It can be difficult for our human eyes (as opposed to a camera lens) to disperse the flashes of white light into colored light / sparkle. Thus princess cut diamonds with four chevron facets can appear to be more brilliant (white sparkle) than exhibit a virtual balance of brilliance and dispersion (colored sparkle / fire) and the diamond usually exhibits more of a crushed ice look.

Three chevron princess cut diamonds:

I personally prefer princess cut diamonds that feature a 3+1 combination of a pavilion main facet that is accented by three chevron facets. This 2.051 carat, G-color, VS-1 clarity, Brian Gavin Signature princess cut diamond is an example of a princess cut diamond that features three chevron facets.

Three chevron facets tends to produce larger virtual facets, which provide a balance between the 2+1 and 4+1 facet configurations. This creates princess cut diamonds that look brighter. The sparkle is larger in size, bolder, brighter, and more vivid than what two and four chevron princess cut diamonds display.

The same premise holds true for round brilliant cut diamonds by the way, and this is where the research began. When the lower girdle facet (LGF) length of a round is between 75 – 78% and combined with ideal proportions in the center spectrum of the range, then the diamonds produce the same kind of broad spectrum sparkle. When the LGF’s are lengthened to 80 – 82% the size of the sparkle diminishes, and the diamonds start to look more brilliant and resemble crushed ice. This is outlined in the article 15 Seconds to Diamond Buying Success. Princess cut diamonds that feature four chevron facets tend to look like crushed ice.

Development of the Brian Gavin Signature Princess:

If you look at princess cut diamonds cut earlier by Brian Gavin, such as this 2.497 carat, G-color, VS-1 clarity, BGD Signature Princess cut diamond, you’ll see that they featured a 2+1 facet structure. This gives you an opportunity to compare images for a 2+1, 3+1, and 4+1 pavilion designs and determine which one appeals to you most. Pay particular attention to the amount of red indicted in the ASET image, and the pattern of how the red, blues, and greens, are dispersed throughout the diamond — refer to this article for what the different colors of ASET mean.

Notice that all of the new BGD Signature Princess cut diamonds feature a 3+1 facet design. The research conducted by BGD during their development process all indicates that this combination produces the highest volume of light return, and superior sparkle.

The thing with Brian Gavin Princess cut diamonds is that they are all being produced under the direction of Brian Gavin. The diamonds are all cut in the same diamond cutting factory, thus the ASET and Ideal Scope images for all the new 3+1 chevron facet / pavilion main facet BGD Signature Princess cut diamonds look quite uniform.

AGS ASET and Princess Cut Light Performance:

Take a look at how consistent the ASET images look for these Brian Gavin Signature Princess cut diamonds, which all feature the three chevron facet structure:

Search Brian Gavin Signature princess cut diamonds, three chevron facet ASET scope comparison chart

Now go compare this with the ASET images provided for other brands of princess cut diamonds. Tell me whether you see this type of consistency. This tutorial about what the different colors of an ASET image mean will provide more insight on how to interpret these images.

Choosing the best princess cut diamonds:

It goes without saying that a critical part of choosing the best princess cut diamond is knowing the type of light performance and sparkle factor that you prefer. Obviously Paul Slegers of Crafted by Infinity preferred the sparkle factor of princess cut diamonds polished with two chevron facets. That is why his production of princess cut diamonds featured two chevron facets.

Brian Gavin has produced princess cut diamonds with two chevron facets, three chevron facets, and four chevron facets. Eventually he decided that three chevron facets produces the best balance of brilliance and dispersion, and sparkle that is perfect in terms of intensity and size.

Having had the opportunity to examine thousands of princess cut diamonds over the years, I have to agree with Brian Gavin. I think that three chevron facets creates sparkle that is the perfect size. This combined with the right proportions creates a virtual balance of brilliance and dispersion. That’s pretty difficult to find in a princess cut diamond. The majority of which are not cut for light performance.

I’m reminded of the story of Goldilocks and the 3 bears. No doubt you know all about the whole porridge incident. But did you also know that Goldilocks was part of the Bling Ring? After eating her fill of porridge, Goldilocks wandered upstairs and spent the afternoon trying on clothes and jewelry.  Inside Mama Bear’s jewelry box, she found three princess cut diamond rings. One princess cut diamond featured two chevron facets. One princess cut diamond featured three chevron facets. And one princess cut diamond featured four chevron facets.

She tried on the princess cut diamond with two chevron facets and exclaimed “Oh my, the sparkle is a little bit too big, and a bit too flat in appearance.” She tossed it aside and it rolled under the bed.

She tries on the princess cut diamond with four chevron facets and exclaimed “This one looks like crushed ice. The sparkle is too small, and there isn’t much dispersion.” She tossed it over her shoulder. It flew right out the window and landed on the front steps of the cottage where it was later discovered by the bears as they returned home…

Goldilocks tried on the Brian Gavin Signature princess cut diamond that features three chevron facets, and exclaimed that everything about it was just right. The sparkle was not too large, nor too small. The reflections of light were evenly distributed throughout the diamond. The diamond exhibited the perfect balance of brilliance and dispersion. She snuggled down with it beside the fire, mesmerized by how her diamond plays with the light. She fell asleep so soundly that she didn’t even stir when the three bears returned home. Goldilocks was never seen, nor heard from again.

The moral of the story is that you should buy a Brian Gavin Signature princess cut diamond that features three chevron facets. What else could the moral possibly be? It’s not like anybody actually eats porridge anymore.