5 Ways to Distinguish Between Lab-Grown & Natural Diamonds

Spotting the difference: Lab-grown and natural diamonds...

Technology has come so far in gemology and jewelry making over the last few decades! Nowadays, experts can utilize software and enhanced tools to cut diamonds with lasers, remove imperfections, and produce intricate settings to craft the ring of your dreams. However, the most fascinating find to come out of this diamond renaissance is lab-grown diamonds.

Today’s lab-created diamonds are identical to natural stones, but there are a few ways you can distinguish between the two with the right tools and paperwork. If you’re searching for a new diamond, here are 5 ways to tell whether you’re looking at a lab-grown or natural gem.✅

An overview of lab-grown diamonds

So what exactly is a lab-created diamond? Lab-grown diamonds are identical to natural ones chemically, physically, and visually. However, instead of relying on the painstaking mining efforts used to retrieve natural diamonds, experts craft lab-created stones in a lab via a few different processes.

The two main manufacturing processes used to create lab-grown diamonds are High Pressure, High Temperature (HPHT) and Chemical Vapor Deposition (CVD).

• For HPHT, scientists replicate the natural process of diamond formation in a lab. They utilize temperatures of 1300-1600℃ and pressures of 5-6 GPa to form diamonds from carbon, which is similar to the high heat, high pressure environment that produces natural diamonds. However, instead of millions of years, the process takes mere weeks!
• CVD is a newer manufacturing process that requires slightly lower temperatures—roughly 700-1300℃—and a special chamber-like structure to produce diamonds. After placing a diamond seed in the chamber, scientists then pump carbon-filled gas into the space that ionizes and allows the carbon to deposit onto the seed freely, slowly building into a diamond.

Both processes result in a lab-grown diamond that’s 30-50% cheaper than natural stones and more environmentally friendly depending on the process used to create it. As time goes on, lab-grown diamonds are becoming incredibly popular, and consumers are realizing that a diamond with natural origins isn’t necessarily better than a lab-created stone!😎

How can you distinguish between lab-grown and natural diamonds?

Experts and shoppers alike cannot distinguish a natural diamond from a lab-created stone with the naked eye. Instead, the best way to figure out whether you’re looking at a lab-grown diamond is to closely inspect the gem’s official paperwork. This can be done in two different ways:

Find the diamond’s laser inscription

Using a diamond loupe or microscope, you or a jeweler can view the diamond’s laser inscription to find out whether it is lab-grown. All lab-created diamonds include a statement detailing their lab-grown status within the inscription on their girdle. This information is typically followed by the diamond’s report number, which can be typed into a database to track down the stone’s official diamond report.

Check the diamond report

If you already have a diamond report handy, you can utilize it to learn more about the specs of a particular diamond as well as whether it is lab-grown or not. Diamond reports include important details regarding dimensions, proportions, the 4Cs, fluorescence, and more; most versions even contain a diamond plot that maps out inclusions and blemishes.

Two famous diamond graders, the Gemological Institute of America (GIA) and the International Gemological Institute (IGI), pride themselves on providing extensive diamond reports and rigorous examinations of each diamond that enters their labs.

When it comes to the GIA, their lab-grown diamond reports provide the standard information mentioned above for loose, lab-created diamonds over 0.15 carats. They use the same scale to grade the color and clarity of lab-grown stones as they use for natural gems, but the grade does not denote any “rarity” as it would for a natural diamond. The GIA also clearly marks these stones as “Laboratory-Grown” within their girdle inscription.

The IGI is similarly thorough, providing grades for each characteristic of lab-grown diamonds. Furthermore, to avoid confusion, the IGI ensures that all lab-grown diamond reports are yellow rather than white, further denoting the stone’s lab-created status. Each diamond also includes a “Lab-Grown” inscription next to its report number on its girdle.

How do gemologists tell the difference between natural and lab-grown stones?

Gemologists have more tools at their disposal for identifying lab-grown diamonds. While they still cannot see differences between lab-grown and natural stones with the naked eye, they can locate specific markers within the stone that can denote its lab-created nature.🔬 Here are three ways gemologists can distinguish between lab-grown and natural stones:

Types of inclusions

While there are no easily visible differences between lab-grown and natural diamonds, gemologists can sometimes study each stone’s inclusions to make an educated guess regarding its origins. Using a microscope, gemologists can examine the tiny imperfections within each diamond, some of which only appear in lab-created gems.

Natural diamonds may contain feathering, clouds, pinpoints, crystals, and a host of other inclusions. ⚠️However, metallic inclusions are unique to lab-grown stones, and the presence of these imperfections can tip off gemologists regarding a stone’s growth morphology.

Nitrogen levels

Another way gemologists can discern whether a diamond is lab-grown or not is by looking for a high level of nitrogen within the stone. As natural diamonds form under intense heat and pressure within the earth, they’re sometimes exposed to nitrogen. The level of nitrogen in a natural diamond can vary, but high levels of it can give diamonds a yellowish hue.

In contrast, lab-grown diamonds don’t always contain nitrogen, as they’re not made deep within the earth’s crust. So, if a gemologist can determine the absence of nitrogen, they can assume a diamond is lab-grown.

Strain patterns, color zoning, and ultraviolet fluorescence

The final way gemologists can detect lab-grown diamonds is by looking for strain patterns, color zoning, and ultraviolet fluorescence. In addition to distinguishing between natural and lab-grown stones, these differences can even help identify growth morphology in lab-created diamonds.

Strain Patterns

Both natural and lab-grown diamonds can have strain patterns, but they look rather different when observed with a microscope. Natural diamonds contain a crosshatched strain pattern as a direct result of intense pressure during the formation process.

However, strain patterns in lab-created diamonds don’t have this unique, crosshatched look. Lab-grown diamonds made using CVD have “banded” patterns, and HPHT lab-created diamonds have little to no strain pattern at all thanks to the uniform pressure they experience during formation.

Color Zoning

Color zoning refers to the diamond’s color distribution based on the concentration of other elements within the stone. When observing the color zoning of natural and lab-grown diamonds, gemologists will notice:

Ultraviolet Fluorescence

Lastly, lab-created diamonds undergo different fluorescence than natural stones. Natural diamonds experience stronger fluorescence while viewed under long-wave ultraviolet light, but the opposite is true for lab-grown stones. Consequently, lab-grown diamonds fluoresce stronger under short-wave ultraviolet light.

What’s more, lab-grown stones have different patterns of fluorescence based on their growth morphology. HPHT diamonds have a cross-shaped pattern that appears over the pavilion or crown, whereas CVD gems produce a striped pattern instead.

Understanding the FTC's rules on advertising lab-grown diamonds

Typically, reputable retailers are very transparent regarding each diamond’s origin, but some sellers aren’t as forthcoming. As a result, the FTC has specific guidelines regarding how companies can advertise their lab-grown stones.

Diamond retailers use the FTC’s “Jewelry Guide” as a handbook for creating marketing materials related to the sale of all types of jewelry. Because lab-grown diamonds are a newer addition to the market, the wording surrounding a lab-grown stone’s origins must be clear to avoid misrepresenting the product.

According to the FTC, all lab-created diamonds should be described as “laboratory-grown”, “laboratory-created”, or “[manufacturer name]-created”, and this phrase should appear before the word “diamond” in the product label, description, etc. Other words or phrases may be used before the word “diamond” if they properly disclose the nature of the gem and the fact that it is not a natural diamond.

Retailers may also refer to lab-grown diamonds as “cultured” so long as the phrase is followed by a clear description of the diamond’s origins or utilizes any of the above phrases. However, these rules only apply to lab-grown stones that are physical, optical, and chemical copies of actual diamonds, and “synthetic” gems have their own rules.

Furthermore, this information must be plainly available in ads, product descriptions, and anywhere a consumer may view the diamond. These “truth-in-advertising” rules also apply to social media, where even sponsored posts on Facebook, Instagram, and Twitter must denote the diamond’s lab-grown nature. In short: it cannot just be hidden in a hashtag!🙂

Finally, if a lab-grown diamond is advertised as “eco-friendly” the company must explicitly state HOW that is true: does the manufacturing process waste less water? Less energy? Advertising must be clear regarding “eco-friendly” status, and the retailer must offer materials that verify their claims.

Lab-grown diamonds: An affordable alternative to natural gems

While no one wants to be unpleasantly surprised by a lab-grown diamond when they thought they were purchasing a natural one, these lab-created stones have plenty of benefits and should be considered as an alternative to regular diamonds. Lab-grown diamonds are affordable, readily available, and environmentally friendly. If you’re looking for an exact replica of a diamond with a smaller price tag and significantly tinier footprint (in most cases), lab-grown stones are the way to go!

When it comes to buying lab-created diamonds, you should definitely still follow the 4Cs of quality diamonds. We recommend reading our lab-grown diamond guide before making a purchase to give you more insight into lab-created gems.