Try to search for an excellent cut diamond on stores like James Allen or Blue Nile, then narrow down search to show diamonds with symmetry of “Good”, you will either find a few, or none at all!
Here is a pre-defined search on James Allen that includes any color, clarity, carat, cut, whatever, but just with a filter for good symmetry.
As the time of writing this, you can see around 5000 diamonds with Good symmetry, just filter out Ideal (and of course True Hearts™) cuts, and see if you get ANY diamond!
Good Symmetry & Excellent cut are very rare to be found together, because of the huge influence of “bad” symmetry (a.k.a good only) on the cut!
While an untrained eye might not tell a good symmetry by just looking at the diamond like this one but it’s very important to note this feature very well, and this is what our post about.
What is Diamond Symmetry?
Symmetry refers to how well the facets and angles of the diamond align. Since the sparkle and beauty of a diamond are determined by how well light reflects through it, a diamond with “better” symmetry will be more sparkly than one with a poor symmetry.
To understand symmetry better, always remember what it meant back when you were in school, symmetry in math means that an object is identical in both of its halves against a column in the middle.
Just look at this image and you will totally understand why symmetry in diamonds is important, just follow the light (in an excellent symmetry), and then think of a diamond that has poor symmetry (two facets against each other, but not in the same angle, the light will not reflect as it should) that misdirects the light travels to the diamond and results in sending it to wrong angles which in fact will make the diamond less sparkly.
What Are The Diamond Symmetry Grades?
Diamond Symmetry Grades are determined by The GIA, under 10x magnification are divided into Excellent, Very Good, Good, Fair and Poor.
To measure the Diamond Symmetry, the Gemologist examines several features to determine the grade of symmetry, such as:
1- The size and shape of the diamond facets.
2-The alignment of the crown and pavilion.
3-The place of the culet sits compared to the table.
As for The Symmetry Grading Scale: (under 10x magnification)
- Excellent: there are no symmetrical defects.
- Very Good: “extremely” difficult to see defects.
- Good: difficult to see defects.
- Fair: defects are noticeable and may be visible to the naked eye.
- Poor: defects are visible even to the naked eye ( the diamond is likely to look dull).
What Diamond Symmetry to Look For?
In general I recommend buying a diamond with a symmetry rating of “Very Good” or better. All other things being equal I wouldn’t pay more for a diamond with an Excellent grade – why?
Because as with so many things when it comes to diamonds you have to understand the circumstances in which these grades are given. GIA and AGS (or any other lab for that matter) are inspecting diamonds under extreme conditions using extremely powerful magnification and ideal reference diamonds.
It is hard for some Gemologists to distinguish between a “Very Good” and “Excellent” symmetry, therefore there is no need to spend an extra amount of money to buy that diamond with the Excellent symmetry grade. Therefore the average consumer will not be able to tell the difference between a Good rating and an Excellent rating. Why pay more for something you will never see and only exists on a piece of paper?
But bear in mind, it is NOT the same for Fair and Poor symmetry grade, since the defects are visible to the naked eye.
Should I buy a diamond based on its Symmetry?
The answer is NO. There are various and more important factors that affect the quality of a diamond, such as the 4Cs. Educate yourself about diamonds before heading to a jewelry shop whether an online or physical one, because a diamond is chosen or rejected based on the quality of those 4Cs in the first place, afterward comes comparing the symmetry of diamonds as a further filtration.
Our favorite online diamond selling stores are James Allen and Blue Nile, present the option to compare and filter the characteristics of each diamond of their enormous collection based on your needs and interests.
A diamond with a symmetry rating of V. Good and higher is an excellent choice and will not cause any noticeable negative effect on the light performance of your diamond!