How to Examine a Diamond
When buying a diamond, examine it loose (not mounted in a setting) as a professional diamond buyer does: with proper lighting conditions and proper tools. Judging a diamond in this way will give you a true understanding of the intricate details that make each diamond unique.
At Robbins Brothers, you can examine the diamonds you are considering in our private diamond viewing room with our certified diamontatologist. Our experts love to share their knowledge and experience. Below are a few things you find useful to know.
Should I view a diamond under a microscope when shopping?
Yes, you should view the diamond under a stereo binocular microscope at ten power (10x) magnification with a stable light source and two eyes looking at the diamond. This will allow you to judge a diamond properly.
Why is 10x magnification of a diamond the industry standard?
Ten times magnification under a microscope is the standard magnification in the diamond industry as a result of the creation of the Clarity Rating Scale. This scale is the standard used throughout the diamond industry.
A diamond rated “flawless” has no visible markings under 10x magnification. (At greater magnification, any diamond may have some markings as diamonds are a natural substance.)
While some jewelers examine diamonds with a handheld 10x loupe, it’s not a good option for those purchasing a diamond. A loupe it doesn’t have a light source, and can be difficult to keep steady. Reputable jewelers will have a stereo binocular microscope at 10x magnification (known as a gemscope) available for you to view diamonds. This type of equipment is stable, has a light source, and allows you to examine the diamond with both eyes at once, which enables three-dimensional viewing so you can examine depth along with other characteristics.
Does it matter under what light I view the diamond?
Yes. In fact, when purchasing your diamond, you should actually see it under different light sources and in a color grading tray. Ensure that you don’t judge a diamond by the color it appears to be in a display case, since the apparent color is influenced by the LED lights in the case.
Use a laboratory light that bleaches out all color except for the actual color of your diamond.
View the diamond under natural conditions such as sunlight (since that’s how the diamond will be viewed under normal conditions).
What should I focus on when looking at a diamond under magnification?
Clarity - look at what’s in the diamond. Most diamonds have minor inclusions. These internal markings are valuable in identifying your diamond because no two diamonds have inclusions in exactly the same place.
Surface or Structural Markings - look for surface abrasions, nicks, cavities or cracks that may impact the structural integrity of the diamond, as well as marks that impact the diamond’s beauty and brilliance.
Entirety of the diamond - don’t just look at the top of the diamond. Look at each layer and the overall interior.
Should I review the carat weight?
Yes, after you have compared the diamonds under the gemscope, look at the carat weight of each. The difference of a point or two can significantly change the cost of a diamond.
Can I view a mounted diamond?
When viewing a loose diamond, you should always view it unmounted (or “loose”), so that you can fully examine the diamond. You can also view a diamond already mounted in a ring (as part of a complete ring with the center stone already included), but keep in mind the following differences:
Look for inclusions visible on the top or sides of the stone and whether they impact the light reflection and make sure you review the grading report for specifics of inclusions.
Compare the diamond color against other diamonds or a white background since yellow and rose gold settings can make the diamond appear whiter.
Check for chips or cracks near the girdle (edges), which can be hidden by prongs.
Ensure the prongs or bezel holds the diamond firmly without gaps.
Once you’ve learned about diamonds, check out the rest of our jewelry buying guides.
