What Is a Lab-Grown Diamond?

Lab-grown diamonds are diamonds—optically, physically, and chemically identical to natural diamond, but created in controlled environments using advanced technology. They’re not fakes or imitations - They are created above ground instead of deep in the Earth.

Types of Lab-Grown Diamonds

  • Chemical Vapor Deposition (CVD)

    • Grows diamonds layer by layer from gas in a vacuum chamber.

    • Produces high-purity stones with fewer inclusions.

    • Often undergos HPHT post-treatment to enhance color.

  • High Pressure High Temperature (HPHT)

    • Mimics natural diamond formation with extreme pressure and high heat in a capsule.

    • Grows faster but may have metallic inclusions due to the metal catalyst used for growth.

    • May have a slight yellow or brown tint but can be grown as colorless.

Natural vs Lab-Grown Diamonds: What's the Difference?

It’s not about better or worse—it’s about what’s right for your customer. Natural diamonds form over billions of years at depths more than 93 miles beneath the Earth’s surface, while lab-grown diamonds are created in weeks using high-tech equipment. Both are genuine; your choice should reflect your customer’s preferences, budget, and expectations.

The most important thing?

Know what you have and disclose it clearly.

Protect your reputation. Mistakes happen. Parcels can contain unexpected lab-grown stones—or even simulants. These tools help you stay one step ahead by confirming what you’re working with before it's set, sold, or returned.

Our Most Trusted Diamond Testers

  • Gemlogis Belize Synthetic Diamond Segregator

    • Test stones as small as 0.02 ct (1.5mm) in the D–J color range

    • Quickly distinguishes between natural diamonds, moissanite, and lab-grown stones.

    • Great for jewelers who need portability and quick results.

    • Tip: Fully charge for the most accurate readings.
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  • Yehuda Sherlock Holmes 4.0 & Dr. Watson

    • Ideal for front-of-house and repair intake

    • Tests loose stones in those mounted in finished jewelry.

    • Uses your phone's camera and an app to analyze phosphorescence

    • HPHT stones show red; CVD stones show other colors. Blue is natural.

    • Tip: Remove your phone case before testing.
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  • Diasynth Diamond Verification Spectrophotometer

    • Professional-grade, AI-powered verification.

    • Uses UV-induced fluorescence photography and advanced imaging.

    • Captures 5 precisely timed UV photos to evaluate diamond origin.

    • Icons to indicate for CVD, HPHT, natural diamonds, and simulants (CZ, white sapphire, and more).

    • Fast, bulk testing with color-coded sorting display.
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Frequently Asked Questions

Do I need a tester if I’m buying from trusted sources?

Yes—mistakes, mix-ups, and undisclosed stones can happen. Diamond verification protects your reputation.

Can I use these testers for repair intake?

Absolutely. Tools like the Yehuda or Diasynth allow you to create a record in a pdf that verifies stones before and after a repair.

How do I tell if a stone is a simulant like CZ, moissanite, or white sapphire?

Simulants can look deceptively similar to diamonds but behave differently under testing.

  • White Sapphire has a much lower refractive index and is doubly refractive—easily detected with a polariscope.

  • Cubic Zirconia (CZ) usually has rounded facet junctions visible under 10x magnification.

  • Moissanite is also doubly refractive and can be detected with basic gemological tools.

Most handheld gem testers can distinguish simulants from real diamonds quickly and affordably, making them a smart investment for any store doing intake, evaluations, or sales.

What if I want an official lab report?

For full gemological certification submit your diamond to the GIA. Learn more here ›

Gemological Tools and Equipment

Our gemological equipment collection features precision tools like Digital Scales, Microscopes, Diamond Testers, and Loupes to support accurate gemstone analysis and grading.

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