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Which ideal cut diamond should I buy?

Which ideal cut diamond should I buy?

“I’m shopping for a diamond engagement ring, and am a bit perplexed about the different descriptions that I’m finding for different types of ideal cut diamonds, and am wondering which ideal cut diamond should I buy? It seems like there is a basic classification of ideal cut diamonds, and then there are sub-categories of ideal cut diamond, such as Hearts and Arrows, Super Ideal Cut, Tolkowsky Ideal Cut, 60/60 Ideal Cut, AGS Ideal Cut, and GIA Excellent Cut. I’m kind of confused about what type of ideal cut diamond I should buy, given all the different types that are available, how should I decide which one to purchase? Regardless of the classification, what I really want is an ideal cut diamond that sparkles like crazy!”

Classifications of Round Brilliant Ideal Cut Diamond:

There certainly are a lot of different descriptions and marketing terms being used to describe ideal cut diamonds, but several of them overlap, and others are often mis-used based upon how we’ve seen other online diamond dealers use the terms, including a third tier gemological laboratory, which in our opinion, has stretched the parameters for the Tolkowsky Ideal Cut diamond, well beyond the range that most people would likely find to be within tolerance of Tolkowsky’s Diamond Design.

Generally speaking, an ideal cut diamond is one that has been cut with a table diameter, crown angle, pavilion angle, girdle thickness, and culet size, that has been proven to deliver the highest volume of light return; unfortunately the range of proportions that is used to define the parameters for an ideal cut diamond, has been adjusted and expanded over the years, and what is now considered to be an ideal cut diamond by many, would not have made the grade just a few years ago.

The Tolkowsky Ideal Cut Diamond Design:

It seems to me that the Tolkowsky Cut Diamond is as good a place to start as any, since many people credit Marcel Tolkowsky with creating the design for the ideal cut diamond back in 1919. Tolkowsky’s Diamond Design is a diamond that is essentially cut to the center “sweet spot” of what is now the basis for the zero ideal cut proportions range designated by the American Gem Society Laboratory (AGSL).

However Tolkowsky’s Diamond Design did not account for the girdle edge of a round brilliant cut diamond, and thus modern ideal cut diamonds, such as Brian Gavin Signature Hearts & Arrows diamonds, are cut within tolerance of that design.

Hearts and Arrows Super Ideal Cut Diamonds:

The term super ideal cut diamond is generally used to describe diamonds like Brian Gavin Signature round diamonds, which are cut to the center range of the proportions parameters used to define and ideal cut diamond, and which exhibit a crisp and complete pattern of hearts and arrows when viewed while unmounted through a hearts and arrows scope.

It is a common misconception that all round brilliant cut diamonds that are cut to ideal proportions, and which have been graded as either AGS Ideal-0 or GIA Excellent Cut, will automatically exhibit a crisp and complete pattern of hearts and arrows; however this assumption is completely erroneous, as a true hearts and arrows diamond can only be created by cutting the diamond to exhibit an extremely high degree of optical precision, which goes well beyond GIA Excellent or AGS Ideal polish and symmetry.

GIA Excellent Cut and AGS Ideal-0 Cut Diamonds:

The terms GIA Excellent Cut and AGS Ideal-0 Cut are not really types of ideal cut diamonds, but rather descriptions that refer to diamonds that have received the highest grade of GIA Excellent from the GIA Gem Trade Laboratory, or AGS Ideal-0 from the American Gem Society Laboratory.

It seems that some jewelers and online diamond dealers operate under the assumption that GIA Excellent and AGS Ideal-0 cut diamonds are the same thing, however this is also not true. Only the AGS Laboratory uses Angular Spectrum Evaluation Technology (ASET) to measure diamonds for brightness, and this state-of-the-art Light Performance technology, prevents a lot of “ideal cut diamonds” from making the grade of AGS Ideal-0 Cut – which is why a lot of diamond cutters send their production to the GIA to be graded as GIA Excellent.

The Infamous 60/60 Ideal Cut Diamond:

The 60/60 ideal cut diamond is a myth, kind of like a unicorn, which must have been created by diamond dealers who simply wanted to be able to label anything that had a total depth and table diameter of around 60% as being an ideal cut diamond, because that is what the description of a 60/60 ideal cut diamond.

Obviously it defies logic that a diamond can be cut to ideal proportions, simply because it has a specific total depth and table diameter, since the pavilion angle, pavilion depth, crown height, and crown angle, will be different from stone to stone, and dramatically so from what we’ve seen…

Brian Gavin Signature Hearts & Arrows diamonds:

While we are clearly biased, the reality is that Brian Gavin is recognized throughout the diamond industry as setting the standard for Hearts & Arrows Diamonds, which are the most precisely cut ideal cut diamond on the market today!

Every Brian Gavin Signature round ideal cut diamond is cut to proportions that represent the center “sweet spot” of the range that defines the zero ideal cut proportions rating established by the AGS Laboratory, and every diamond is graded on the Light Performance grading platform, which relies on ASET to determine that the diamond is delivering the highest volume of light return.

I suppose that you could say that every Brian Gavin Signature round diamond is an ideal cut diamond, a super ideal cut diamond, and a hearts & arrows diamond, and every one of them is cut within tolerance of Tolkowsky’s Diamond Design; so you need not look further if you are truly looking for the best.

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