One Carat Diamond Solitaire Ring for a New Year’s Engagement:

“Hi Todd, I’m planning on proposing to my girlfriend on New Year’s Eve. I would appreciate some help because I seem to be stuck in a state of analysis paralysis. Thanks in part to the information provided on your website.”

“What I’m looking for is a one-carat round diamond solitaire engagement ring in the range of G-H color, and VS-2 clarity, set in an 18k yellow gold setting. I read your One Minute Diamond Buying Guide and took note of your preferred range of proportions and found several suitable options from the vendors which you recommend. Here are the diamonds which I am considering, what do you think? — Kevin J.”

Cherry Picking the Best Diamonds from each vendor:

Kevin writes: Using the selection criteria which you outlined on your website, I did my best to cherry-pick the best that each vendor had to offer in terms of round brilliant ideal cut diamonds in the range of one carat, G-H color, and VS-2 clarity. Here are the diamonds which I chose from the inventory of the vendors which you seem to prefer:

1.013 carat, G-color, VS-2 clarity, Brian Gavin Signature Diamond with medium blue fluorescence.

1.038 carat, G-color, VS-2 clarity, Hearts & Arrows Diamond from Crafted by Infinity via HPD.

1.132 carat, G-color, VS-2 clarity, Brian Gavin Signature Hearts & Arrows Diamond.

1.135 carat, H-color, VS-2 clarity, Hearts & Arrows Diamond from Crafted by Infinity via HPD.

1.138 carat, H-color, VS-2 clarity, True Hearts Diamond from James Allen.

Note that I edited the structure of the diamond description for the links…

Tips for Buying a Stunning Diamond Engagement Ring:

As you indicated above, there is a set of proportions that I like to adhere to when shopping for round brilliant ideal cut diamonds, which I find works extremely well for selecting diamonds that exhibit the highest volume of light return, that set of proportions is outlined as follows:

  • Total depth between 59 – 61.8%
  • Table diameter between 53 – 57%
  • Crown angle between 34.3 – 34.8 degrees
  • Pavilion angle between 40.6 – 40.9 degrees
  • Girdle thickness between thin and slightly thick
  • Culet: AGS pointed or GIA none

This specific set of proportions is equivalent to the bulls-eye that appears as the center ring on a target,  it is the “sweet spot” which every diamond cutter knows that they should strive for when cutting round brilliant ideal cut diamonds, but which they often stretch beyond in order to maximize the retention of diamond carat weight during the cutting process. But a few diamond cutters like Brian Gavin and Paul Slegers of Crafted by Infinity, have consistently chosen to focus on the light return and visual performance of the diamonds that they produce, rather than the final yield of carat weight.

While it is true that there are other combinations of crown and pavilion angle that produce an excellent volume of light return, the reality is that it takes a lot of experience to know exactly which specific combinations will yield similar results as the center range of proportions which I’ve outlined above, and I find that most consumers lack that type of in-depth experience that comes from being a veteran diamond buyer with almost 30 years of experience.

What do the different colors of an ASET mean? Brian Gavin Diamond with medium blue fluorescence, AGSL 104055121006I am partial to the diamond grading practices of the American Gem Society Laboratory (AGSL) and the Gemological Institute of America (GIA) because I find their grading to be consistent and reliable. I generally prefer diamonds graded by the AGSL with an overall cut grade of AGS Ideal-0; as determined on their Proprietary Light Performance grading platform, which uses Angular Spectrum Evaluation Technology (ASET) to measure the brightness of a diamond, and which provides insight into the optical symmetry of the facet structure. Refer to my article What do the different colors of an ASET mean, for a full explanation of how to understand the ASET image pictured to the left.


The ASET image featured above is from the 1.013 carat, G-color, VS-2 clarity, Brian Gavin Signature Diamond with medium blue fluorescence, which we’ll get into in just a moment. In addition to offering diamonds which are graded by the AGSL, Brian Gavin also provides images of the diamonds as seen through the various reflector scopes which are used to judge the level of optical symmetry of the diamond, such as an ASET Scope, an Ideal Scope, and a Hearts & Arrows Scope.

If the diamond is graded by the GIA, then I prefer that it have an overall cut grade of GIA Excellent and that the seller provide images of the diamond as seen through the various reflectors scopes mentioned in the last paragraph. However, I’ve noticed that the majority of online diamond vendors do not provide reflector scope images of the diamonds which they represent, most likely because they realize that doing so causes people to question the cut quality of their diamonds due to the inconsistency of the patterns exhibited.

Considering the Characteristics of Each Diamond:

All right, let’s get down to brass tacks and look at the characteristics of each of the diamonds which you’ve selected, the first thing I noticed is that all of them are graded by the American Gem Society Laboratory (AGSL) with an overall cut grade of AGS Ideal-0, and cut within my preferred range of proportions, so we don’t need to get into those details because everything is spot-on. Taking the diamonds in the order of carat weight, as they are presented:

What does medium blue fluorescence in a diamond look like? Brian Gavin Diamonds AGSL 104055121006The 1.013 carat, G-color, VS-2 clarity, Brian Gavin Signature Diamond with medium blue fluorescence is definitely a diamond which I would choose myself because I’m a huge fan of diamonds with blue fluorescence. The medium blue fluorescence might even give the G-color a little boost towards the high side of the G-color range. The primary inclusions consist of diamond crystals; clouds, which are simply small clusters of pinpoint size diamond crystals; and needle-shaped diamond crystals; which happen to be my favorite type of inclusions because they are simply tiny diamonds that were trapped within the larger diamond crystal as it formed.


As with all of the diamonds featured within the Brian Gavin Signature and Brian Gavin Blue collections, the diamond details page provides a three-dimensional video of the diamond which shows the vivid contrast and sparkle created by the exceptional optical symmetry that this diamond has been cut to.

Diamond clarity photograph, Crafted by Infinity Diamond AGSL 104059209001The clarity photograph provided to the left shows the inclusions within this 1.038 carat, G-color, VS-2 clarity, Hearts & Arrows Diamond from Crafted by Infinity via High Performance Diamonds. The loupe tool provides additional insight by making it possible to view the inclusions at a larger magnification, and the diamond crystals and feather within this diamond look very slight. Although there is not a video of the diamond provided on the diamond details page, I know that Wink will shoot a video of the diamond upon request… just tell him that I said so! Laughs! Who knows, he might even personalize it for you and then you can share it with your fiance after you present her with the diamond!


Hearts and Arrows pattern within Brian Gavin Signature Diamond, AGSL 104064831012As you can see from the picture to the left, the hearts pattern within this 1.132 carat, G-color, VS-2 clarity, Brian Gavin Signature Hearts & Arrows Diamond is absolutely gorgeous! According to a study conducted by the AGSL on the sparkle factor of a diamond, diamonds cut to this level of precision exhibit a higher volume of light return and larger flashes of sparkle. It should be noted that while Brian Gavin does not market the diamonds from the Brian Gavin Blue collection as H&A diamonds, they are produced by the same diamond cutters and the ones which I’ve examined show patterns which are pretty darn good, so I would not hesitate to buy a diamond from either collection.


Hearts and Arrows pattern Crafted by Infinity diamond, AGSL 104067217021 The hearts pattern exhibited by this 1.135 carat, H-color, VS-2 clarity, Hearts & Arrows Diamond from Crafted by Infinity via HPD is equally impressive and it should be noted that I consider the production of Brian Gavin and Paul Slegers to be on equal footing, with no preference for the production of one diamond cutter over the other… my decision to recommend a diamond from Brian Gavin or Crafted by Infinity usually has more to do with the current availability than a difference in production quality. Here again, the primary inclusions are diamond crystals and clouds of pinpoint size diamond crystals so there is nothing to worry about. I’d grab this diamond in a second.


Hearts pattern within James Allen True Hearts Diamond, SKU 261466 You just need to mouse over the hearts and arrows icon provided on the diamond details page in order to see the hearts and arrows image for this 1.138 carat, H-color, VS-2 clarity, True Hearts Diamond from James Allen and when you do so, you’ll see that the pattern is pretty good, with just a little bit of variation in the size and shape of the hearts, as well as a little bending in the tips of the hearts, which is evidence of minor degrees of azameth shift. This is not something that would prevent me from purchasing this diamond, it is merely a characteristic of the overall cut quality of the diamond and I mention it because such things are taken into account at this level of the game.


I have to say that you did an excellent job of selecting some exceptional diamonds from my preferred list of vendors Kevin, and I don’t see the one which necessarily stands out over another. I have to say that if I were still buying diamonds for Nice Ice, that every one of these diamonds would have made it into our inventory… thus how do I pick a favorite?

The proportions are essentially equal, so is the level of optical symmetry with very little variance… and the inclusions are essentially the same… did you select these just to torture me? No wonder you haven’t made a decision, it’s not a matter of analysis paralysis, it’s just a matter of trying to make a choice between five diamonds which are pretty much the same! Honestly, I’d pin this list of diamonds to the wall, blindfold yourself, spin yourself around in a circle three times, and then pin the tail on the donkey… in this particular instance, it’s not a bad way to reach a decision.

More Tips & Tricks from Nice Ice:

Nice Ice Blueprint™

The Nice Ice® Blueprint™.

Super Charge Your Diamond Buying Skills:

Follow the Steps in The Nice Ice® Diamond Buying Blueprint™ and Unlock the Secret for Maximizing Sparkle Factor and Light Performance. These are the Tips & Tricks from the back office of Nice Ice Diamonds.