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Shopping Treated Diamonds? Proceed with Caution

By Stephanie Dore

Chances are, if you’re shopping for a diamond, you’re looking for a good deal. And why not? We all want to get the most brilliance for our bucks. But in that search, you may have come across some great deals for treated diamonds, too. And if you’re a newbie to the diamond game, the words “treated” or “enhanced” might sound a bit sus. Well, darlings, if that’s the case, you’re not wrong for wondering just what treated diamonds are and whether they’re really as great as their price tags. So in the interest of education, here’s a quick rundown of what you should consider before buying a treated diamond of your own.

What Are Treated Diamonds, Anyway?

Treated, or enhanced, diamonds are diamonds that have had their clarity or color enhanced post-growth through various means. This can be done to both natural, mined diamonds and to lab-created diamonds, and is used to improve the clarity or alter the color of the diamond to make it more desirable for the market. And of course, increase the profit margin for the makers. While first quite rudimentary, these treatments have become as sophisticated as other diamond technology, often making treatments difficult to detect by all but the most high-end grading labs.

emerald cut three stone engagement ring
While most high clarity diamonds were born that way, there are ways to manipulate their appearance.
elongated cushion cut solitaire ring
Looking for something hyper-specific on a tight budget? This may be the reason to open your search to treated diamonds.

What Are the Benefits of Treated Diamonds?

The main reason folks purchase treated diamonds is price. Treated diamonds often sell for 30-50% less than non-treated stones, which means that you can get a bigger diamond for your money. And we all know size really does matter — to some. If you are also looking for a very specific diamond color preference within a specific budget, color-enhanced diamonds can sometimes fit the bill.

What Are the Downsides of Treated Diamonds?

While it’s certainly tempting to get a treated diamond for its cost savings, the risks are substantial. First, while most sellers properly disclose any diamond treatments to buyers, there are those that don’t, and unless you’re a super-trained gemologist with lots of expensive gear at your disposal, there’s a good chance you wouldn’t catch it. Second, reputable grading labs like GIA just flat-out won’t issue a grading report if they find that a diamond has unstable or nonpermanent treatments. This is because there’s no way to tell its original state or grade. And third — and most importantly — most treatments are not permanent and can degrade over time or cause greater risk for the diamond, especially if your ring needs to be repaired. And ring repairs are actually kind of inevitable. Why? Well, you wear your rings! It’s just a fact of ring ownership that our hands take a lot of wear, and often small diamonds will need replacement or prong tips will need to be, well, re-tipped. And jewelry repair often requires heat — the enemy of all treatments. But let’s talk specifics.

round three stone diamond ring
If you want to avoid treated diamonds at all costs, keep your search to GIA-graded diamonds!

Diamond Clarity Treatments

There are two main types of treatment to improve diamond clarity. The first is fracture filling — where molten, glass-like substances are injected into a low-clarity diamond’s inclusions, filling them and making the inclusions less visible. This is the most common clarity treatment however it’s also very easily damaged when the diamond is heated or cleaned with ultrasonic or acids. This can either burn the fill substance and turn it dark or the substance can leak out, thus worsening the diamond’s clarity.

The second method of clarity enhancement is laser drilling, during which a manufacturer can lighten or remove a diamond’s dark inclusions by drilling a tiny laser hole through the diamond to the inclusion itself, either vaporizing it or enabling them to apply bleach or acid that lightens the inclusion. While these tiny laser tunnels are not usually eye-visible, they are visible under magnification and are a permanent treatment. Any substance applied via the hole is not, however, permanent and subject to the same risks as fracture filling. These tiny holes, since they are open to the surface of the diamond, can also fill with dirt or debris and appear dark over time.

Diamond Color Treatments

There are a few more variations when it comes to the different ways diamonds can be treated to enhance or alter their color. The first is irradiation — where a diamond is subjected to radiation after its growth (instead of during) — and this can result in a wide range of diamond colors. Irradiation is not permanent. Annealing, a controlled process of heating and cooling a diamond (often used in addition to irradiation) to reach a desired color is another non-permanent treatment.

black diamond halo ring
Most natural black diamonds get that rich color on their own, no need to treat them!

HPHT Treated Diamonds

High Pressure, High Temperature (HPHT) treatment is just like the process used to create lab grown diamonds, replicating the conditions of natural diamond growth, only in a lab. It’s often used to turn brown diamonds colorless or into other colors like green, yellow, pink, blue, or orange. While HPHT is considered a permanent treatment, it is often used in combination with irradiation or annealing which are not.

Diamond Coatings

While this might seem like a strange thing to do, it’s not unheard of. Diamonds have been known to actually be coated in layers of silica to create a wide range of vibrant colors. This color, while durable, is definitely not permanent and can be scratched or damaged by the same heat and chemicals that damage other diamond treatments.

radiant cut lab diamond toi et moi ring
The cool thing about natural fancy colored diamonds is their natural occurring variations!
emerald cut diamond solitaire ring
Fracture filling and other treatments to boost the clarity of a step cut diamond will fade over time, and you’ll be left with a nasty inclusion.

Detection and Diamond Grading

Like we said up top, detecting treated diamonds can often be extremely difficult and sometimes only able to be done by the most highly trained labs with sophisticated equipment. If a reputable lab detects any of these treatments, they will label the diamond as such and not assign it a color or clarity grade. They will often laser inscribe the stone with its treatment type as well, so as to alert anyone else who inspects it.

Should You Buy a Treated Diamond?

We really wouldn’t recommend it. It’s just not worth the risks for something that most folks intend to wear and cherish for life. Especially not when untreated, lab created diamonds can save you just as much money as a natural, treated diamond. If you’re looking for something specific or working within a tight budget, our diamond experts are more than happy to help!

Check out our diamond search where you can view 360-degree images of more than 10,000 diamonds and don’t forget to zoom out (because size can be deceiving), or book an appointment at our New York salon to view certified lab-grown and natural diamonds in person. 

Not finding what you’re looking for? We love hunting down the perfect diamond for your dream ring. Email us with what you’re looking for (and a bit about your budget) at We’ll curate a list of 5-7 exclusive stones that are just right for you.

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