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What Does a Diamond Look Like Through a Loupe?

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man eveluating diamond through loupe

Most diamonds are gem-quality diamonds that have already been cut and polished. Some have been altered slightly more to remove their imperfections (or cover them up). For that reason, when using a magnifying device called a loupe, a diamond will have a faceted look and a specific shape based on how they were cut. 

When buying a diamond, it’s essential you check it for quality first. One of the best tools to check the quality of a diamond is a loupe (aka hand lens). A loupe is a handheld cylindrical device with an optical lens. The optical lens, much like the lens in a magnifying glass or telescope, magnifies the object through the loupe. 

Unlike other magnification tools a loupe is meant to be held very close to the user’s eye and, for that reason, has a much shorter focal length. Typically, a loupe will offer magnification from 10x to 30x. However, most jewelers use a loupe with 10x magnification for the best focal length and clarity.

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What To Look for in a Diamond with a Loupe

You will see several things and hopefully not see when you look at a diamond using a loupe. Seeing the typical crystal structure of a diamond goes without saying. However, some of the other items you might see depend on the diamond and whether it is raw or gem quality.

man holding jewelers loupe and diamond
Image Credit: Nejron Photo, Shutterstock

Raw Diamonds

Using a loupe, you will see that raw diamonds are mostly transparent but usually have a yellow or light brown tint. Some raw diamonds won’t have these slight tints, but they are quite rare. It is essential to note that the more tint a diamond has, the less value it will have after being cut and polished. Under a loupe, a raw diamond will not have the facets seen on a cut and polished gem-quality diamond. A colorless raw diamond, referred to as a white diamond, is extremely valuable as they are incredibly rare. 

Gem Quality Diamonds

Gem quality diamonds stand out with a loupe since they have been cut and polished to give them a specific and typically faceted shape. Under a loupe, the faceted structure of a gem-quality diamond will be apparent immediately. Most will also have very little, if any, yellow or brown tint. Most diamonds with tint are used in industrial applications.

Loupes Diamond
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You May See Diamond Inclusions and Blemishes Under a Loupe

It’s rare to find a perfect diamond since they are formed naturally by the earth under millions of pounds of pressure and extreme heat. Most jewelers will never see a perfect diamond in their lifetime but will see many with imperfections referred to as inclusions or blemishes

Inclusions are typically so small that the only way to see them is by using a loupe. Most minor inclusions won’t affect the overall clarity of a diamond, but larger inclusions will. Also, inclusions are found inside a diamond, while blemishes are on the stone’s surface. Many inclusions are diamond crystals trapped inside a particular diamond when forming (These often look like black dots). Below are the three major types of diamond inclusions:

  • Pinpoint: Black spots in a diamond—also the most common type of inclusion.
  • Cavities: Cavities are small holes in a diamond. It’s rare to see one since most diamonds with cavities are made into industrial tools.
  • Feather: These are tiny cracks can be inside or on the surface of a diamond.

Blemishes are, as we mentioned, found on the outside of a diamond. They include scratches, nicks, chips, and any other imperfections on the stone’s surface.

man using jewelers loupe
Image Credit: Andrey_Popov, Shutterstock

You may See Clarity Enhancements When Looking at a Diamond Under a Loupe

Since most diamonds have flaws, many diamonds go through clarity enhancements before they are sent to the market. Laser drilling and fracture filling are the two most common treatments used to enhance the clarity of diamonds. After being clarity enhanced, a diamond should always be labeled as a CE (clarity enhanced) diamond, and jewelers are supposed to let consumers know of this status by law.

Clarity-enhanced diamonds are incredibly popular, especially among couples purchasing a wedding ring. The reason is simple; a CE diamond will usually be much lower in price than a diamond that didn’t need the treatment, but the diamond itself will still be beautiful to the naked eye.

Under magnification with a loupe, you will see certain things when you look at a CE diamond, including:

  • Very thin channels where gemologists used the laser drill
  • A glass-like substance that reflects light differently from the rest of the diamond. This glass is used for fracture filling and, under a loupe, should be easy to spot.
man evaluating diamond ring
Image Credit: LanKS, Shutterstock

You Should See the Diamond’s Laser Inscription With a Loupe

One last thing you will see when looking at a diamond with a loupe, at least when purchasing a diamond from a jeweler, is a laser inscription. Certified diamonds will almost always have a laser-inscribed combination of numbers and letters. These will (or at least should) match the grading certificate the diamond came with and should be visible on the diamond’s girdle.

A diamond’s girdle is the thin perimeter dividing its top half (the crown) from the bottom (the pavilion). Typically it is also the widest part of the stone and where the diamond makes contact with its setting in a ring. Using a loupe, you should be able to see the laser inscription on the girdle and ensure it matches the numbers and letters on your certificate.

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Final Thoughts

Diamonds viewed with a loupe will have facets, reflect light like a kaleidoscope, and have some (but very little) color. They might have some blemishes and inclusions and also show signs of being clarity enhanced. Lastly, you should see the laser inscription typically inscribed on a diamond marketed to the public.

We hope today’s information about what a diamond looks like under a loupe has been informative and helpful. If you’re gathering this information because you’re planning to get married, congratulations! We hope the diamond you choose shines brightly on your happy union for many years to come.

Featured Image Credit: EgolenaHK, Shutterstock

About the Author Greg Iacono

Greg Iacono is a self-taught writer and former chiropractor who, ironically, retired early due to back problems. He now spends his time writing scintillating content on a wide variety of subjects. Greg is also a well-known video script writer known for his ability to take a complex subject and make it accessible for the layperson.