Hey Todd, I really appreciate all of the information that you share on your web site. I’m in the market for a round brilliant ideal cut diamond engagement ring in the range of 1.00 – 1.20 carats, F-G color, VS-2 clarity, and am wondering what you would “cherry pick” from Blue Nile, Brian Gavin, Crafted by Infinity, James Allen, and “Brand X” [brand name edited]. I’m basically looking for a diamond which you would select yourself if you were looking for a diamond to set in something like this 18k white gold split shank halo style engagement ring from James Allen. My primary focus is the overall appearance of the diamond which should be as bright and sparkly as possible. — Ken D.
Best Proportions for Round Brilliant Ideal Cut Diamonds:
Let’s start by reviewing my selection criteria for round brilliant ideal cut diamonds, because my preferred range of proportions is tighter than the range specified by the American Gem Society Laboratory (AGSL) for their zero ideal cut proportions rating. The range of proportions which I adhere to is based upon computerized modeling and physical evaluation of round brilliant cut diamonds cut within strict tolerance of the diamond design introduced by famed diamond cutter Marcel Tolkowsky in 1919.
My preferred range of proportions for round brilliant cut diamonds is as follows:
- Total Depth between 59 – 61.8%
- Table Diameter between 53 – 58%
- Crown Angle between 34.3 – 34.9 degrees
- Pavilion angle between 40.6 – 40.9 degrees
- Girdle thickness between thin to medium, faceted
- Culet size of GIA none or AGS pointed (same thing)
Needless to say, I prefer an overall cut grade of either GIA Excellent or AGS Ideal-0 based on the combined individual grades for polish, symmetry, and proportions. And I tend to lean towards diamonds graded by the AGSL on their Proprietary Light Performance grading platform because of the additional insight provided by their use of Angular Spectrum Evaluation Technology, which is the multi-colored image provided to the left for this 1.013 carat, G-color, VS-2 clarity, Brian Gavin Signature Blue diamond with medium blue fluorescence. The AGSL uses ASET to measure the brightness of the diamonds which they grade, and to provide insight as to how the diamond is making use of the light which is available to it within the room… do you see how nice and symmetrical the pattern of light return is? This is going to be an extremely bright and vibrant diamond!
My Top 10 Diamond Picks in Order of Carat Weight:
I conducted an in-depth search for round brilliant ideal cut diamonds within the range of 1.00 – 1.20 carats, F to G color, VS-2 clarity, within the range of specifications outlined above and then considered the other characteristics of the diamonds and these are my top ten picks, presented in order of carat weight. All of the diamonds meet my selection criteria for overall cut rating, polish, symmetry, proportions, and inclusions… these are all diamonds which would have been brought in for physical evaluation when I was the diamond buyer for Nice Ice based upon the characteristics stated on the diamond grading reports and reflector scope images when provided.
James Allen True Hearts Diamond:
This 1.005 carat, G-color, VS-2 clarity, True Hearts diamond from James Allen is graded by the AGSL and exhibits a very good pattern of hearts and arrows, as can be seen in the photograph provided to the left which is available by mousing over the icon of hearts and arrows located in the upper right corner of the diamond details page. A vary slight variance in the size and shape of the hearts is visible, as well as slight bending of the tips of the hearts, but it is fairly minimal. The dark spots visible within the hearts pattern is a reflection of the diamond crystals located within table facet which are visible because of the magnification used to take the photo.
Brian Gavin Signature Hearts & Arrows Diamond:
The hearts pattern exhibited by this 1.012 carat, G-color, VS-2 clarity, Brian Gavin Signature Hearts & Arrows diamond is much more precise and even in size and shape, notice how there is no twisting in the tips of the hearts, and there is more consistency in the width of the dark areas separating the hearts which is created by the pavilion main facets… the facet structure of this diamond is more consistent and the indexing of the facets is more precise, which will result in a higher volume of light return and more sparkle. The reason why the two halves of each heart appear slightly different is because each half is a reflection of a different facet, which combine to form a heart.
It would look fantastic in the Belle Micro Pave Split Shank Halo engagement ring from Brian Gavin which is pictured to the left. Brian Gavin Diamonds has their own in-house, state-of-the-art jewelry manufacturing facility and custom design studio. The production quality is top notch and absolutely breathtaking, these rings are not stamped out on a production line and I’ve seen Brian Gavin personally inspect several rings before they were shipped out to clients… it simply doesn’t get any better than this! There are only a handful of companies that I would consider ordering a ring from for my personal use and Brian Gavin is definitely at the top of the list because their work is stunning!
Brian Gavin Blue Diamond w/ Medium Blue Fluorescence:
I absolutely love the idea of this 1.013 carat, G-color, VS-2 clarity, Brian Gavin Blue diamond which exhibits medium blue fluorescence when exposed to black light, as is visible in the photograph provided to the left. It seems like every diamond which I have ever chosen for myself, has exhibited medium to strong blue fluorescence, because I just love the effect which blue fluorescence has upon a diamond! Medium to strong blue fluorescence will typically boost the body color of the diamond to the higher end of the range for that color grade, while not having any negative impact upon the appearance of the diamond. Plus blue fluorescence commands a slight discount!
I’ve always thought that the discount applied by the trade to diamonds which exhibit blue fluorescence is counter intuitive because of the positive effects which blue fluorescence has upon the visual properties of a diamond. However the discount has nothing to do with the visual effects of fluorescence upon a diamond, but rather is the residual result of the decision of an Asian investment firm to omit diamonds with fluorescence from parcels of diamonds which they were offering as an investment opportunity for their clients in the 1970’s which had the unforeseen effect of creating a temporary surplus of diamonds with blue fluorescence.
Diamond dealers at the time began to offer a discount on diamonds with blue fluorescence, which created the perception that there must be something undesirable about diamonds with blue fluorescence, when in fact quite the opposite is true. According to a study conducted by the Gemological Institute of America, fewer than 2% of gem quality diamonds are negatively impacted by the presence of fluorescence, and the majority of those exhibit very strong to distinct levels.
Brian Gavin assures me that he personally evaluates every diamond selected for the Brian Gavin Blue collection to ensure that the fluorescence enhances the beauty of the diamond, and based upon the diamonds which I have evaluated in-person this definitely seems to be true.
Brian Gavin Signature Hearts and Arrows Diamond:
I am equally impressed with the overall cut quality of this 1.016 carat, G-color, VS-2 clarity, Brian Gavin diamond with medium blue fluorescence, which is clearly visible in the ideal scope image provided to the left. Notice the consistency of the pattern created by the light, dark, and white areas throughout the diamond, this is evidence of great attention to detail during the diamond cutting process. Brian Gavin is one of the few online diamond dealers who continues to provide his customers with reflector scope images by which to judge the cut quality of his diamonds. These images enable me to judge the diamond cut quality and recommend his diamonds with confidence.
Brian Gavin Signature Hearts & Arrows Diamond:
This 1.020 carat, G-color, VS-2 clarity, Brian Gavin Signature diamond looks amazing in this clarity photograph and equally stunning in the video which is available on the diamond details page! Just look at how the arrows pattern created by the pavilion main facets POPS because of the heightened level of contrast created by the consistency of facet shape per section and precision of alignment. Contrast is what enables our eyes to see depth and beauty within a diamond. This type of contrast enables Brian Gavin Signature and Brian Gavin Blue diamonds to look amazing in all lighting environments, including the fluorescent lighting used in most offices!
Brian Gavin Blue Diamond with Strong Blue Fluorescence:
If you’re a fan of blue fluorescence like I am, you might like the look of this 1.021 carat, F-color, VS-2 clarity, Brian Gavin Blue diamond with strong blue fluorescence. The strong blue fluorescence is likely to lift the diamond to the high side of the F-color range, especially when the diamond is subjected to strong UV light, such as direct sunlight. All of that red which is visible in the ASET image featured to the left, indicates that the diamond is going to be nice and bright; the color green indicates the areas which are second brightest, and the color blue represents the contrast created by the pavilion main facets. This diamond is going to be bright, white, and full of life!
Crafted by Infinity Hearts & Arrows Diamond:
This stunning 1.038 carat, G-color, VS-2 clarity, diamond from High Performance Diamonds is Crafted by Infinity and exhibits a stunning pattern of hearts and arrows. As you can see from the clarity photograph provided to the left, the diamond exhibits an excellent degree of contrast. And the images of the diamond as seen through an ASET Scope, Ideal Scope, and Hearts & Arrows Scope which are provided on the diamond details page, enable me to judge the optical symmetry of the diamond which is exceptional and well beyond the standards required for the overall cut grade of AGS Ideal-0. Diamonds cut like this should be shipped with sunglasses!
Blue Nile Signature Round Ideal Cut Diamonds:
This 1.05 carat, F-color, VS-2 clarity, Blue Nile Signature Diamond does not exhibit a crisp and complete pattern of hearts and arrows. The variance in the size and shape of the hearts is clearly visible in the clarity photograph from the GCAL report which is provided to the left, however the diamond will still be quite bright and lively because the proportions are well within my preferred range and the overall cut grade of the diamond is GIA Excellent. Diamonds like this are considered to be within the Top 2% of the annual production of round brilliant cut diamonds and tend to be better than what you’ll find in the average jewelry store, but I think that the production of BGD & CBI is better.
The overall cut quality of this 1.15 carat, G-color, VS-2 clarity, Blue Nile Signature Diamond is comparable to the last one, there is clearly visible variance in the size and shape of the hearts which are visible within the clarity photograph provided from the GCAL report pictured to the left. I find this to be pretty typical of the majority of Blue Nile Signature diamonds which I evaluate, if you’re truly looking for diamonds with the highest levels of diamond cut quality and optical symmetry, I would focus on the inventory of Brian Gavin and Crafted by Infinity which are well known for their production of H&A diamonds which are graded by the AGSL on the Proprietary Light Performance grading platform.
These diamonds would look great set in this split shank halo engagement ring designed for Blue Nile by Monnique Lhuillier, the ring features 100 round cut diamonds which are VS-2 in clarity and H-color which are set on all visible sides of the diamond for maximum sparkle! There is also a 1.2 millimeter round pink sapphire set on the underside of the head configuration on both sides of the ring which will be visible from the front and back sides of the finger. These “surprise stones” add just a little bit of unexpected decor to the ring…
Round Ideal Cut Diamond from James Allen:
This 1.160 carat, G-color, VS-2 clarity, Round Ideal Cut Diamond from James Allen is another great contender, the ASET image looks pretty good, and the proportions of the diamond are right in the middle of my preferred range… so the diamond is going to exhibit a high volume of light return and excellent sparkle. I can’t tell you anymore about the diamond cut quality or optical symmetry because James Allen no longer provides reflector scope images on their diamond details pages for diamonds which are not part of the James Allen True Hearts collection. However it has been estimated that fewer than 1% of all round brilliant cut diamonds produced in the average year qualify for the overall cut grade of AGS Ideal-0, so you’re off to a pretty good start! Plus you can always ask James Allen for the scope images, they have been known to provide them on request.
Nice Ice Diamond Concierge Service:
This diamond evaluation is an indication of the type of in-depth evaluation that you can expect when you use our free diamond concierge service to help find the diamond of your dreams. Take the guesswork out of finding a diamond and free yourself up to do the work that you’re supposed to be doing while you’re at work… yea, I know that you’re surfing for diamonds while you’re supposed to be working, where else could you do so without getting busted by your fiance? 😉