What Are Lab-Grown Diamonds? Everything You Need to Know

A lab-grown diamond is a real diamond. Not a substitute, not an imitation, not a "close enough." It has the same crystal structure, the same chemical composition, and the same optical properties as a diamond pulled from the earth. The only difference is where it began: in a controlled laboratory instead of deep underground. If that surprises you, you are not alone. Lab-grown diamonds have quietly become one of the most significant shifts the jewelry industry has seen in decades, and understanding what they actually are is the first step toward making a confident purchase.

How Lab-Grown Diamonds Are Made

There are two primary methods used to create lab-grown diamonds: CVD (Chemical Vapor Deposition) and HPHT (High Pressure, High Temperature). Both produce genuine diamonds, but the processes are quite different.

CVD is the method behind most gem-quality lab-grown diamonds on the market today, including those used by Miorenée. It works by placing a thin diamond seed (a small slice of existing diamond) inside a sealed vacuum chamber. The chamber is filled with a carbon-rich gas, typically methane, along with hydrogen. Energy from a microwave beam superheats these gases to between 700 and 1,200°C, breaking the molecular bonds and releasing individual carbon atoms. Those atoms drift downward and bond to the diamond seed, layer by layer, replicating the crystal lattice of a natural diamond.

The process takes several weeks for a gem-quality stone, though dozens of diamonds can grow simultaneously in a single chamber. The result is a Type IIA diamond, which is the most chemically pure category. Type IIA diamonds are extremely rare in nature (fewer than 2% of mined diamonds qualify), yet the CVD process produces them consistently.

HPHT mimics the geological conditions that form diamonds underground. A carbon source is subjected to pressures exceeding 1.5 million pounds per square inch at temperatures above 1,400°C. This method was the original technique, first demonstrated by General Electric in 1954, and is still used today, though CVD has become the preferred method for producing larger, higher-clarity gem-quality stones.

Are Lab-Grown Diamonds "Real" Diamonds?

This is the question that comes up more than any other, and the answer is straightforward: yes. Lab-grown diamonds are real diamonds by every scientific and gemological measure.

They score a 10 on the Mohs hardness scale, the same as any mined diamond. They exhibit the same brilliance (white light return), fire (spectral light dispersion), and scintillation (the sparkle you see when the stone moves). They are graded using the same 4Cs framework (Cut, Color, Clarity, and Carat weight) by the same independent laboratories, including the GIA (Gemological Institute of America) and IGI (International Gemological Institute).

A standard diamond tester will confirm a lab-grown diamond as a real diamond, because it is one. The thermal and electrical conductivity are identical to a mined stone. Even trained gemologists cannot distinguish between a lab-grown and a mined diamond without specialized equipment designed to detect trace differences in growth patterns.

The Federal Trade Commission updated its definition of "diamond" in 2018 to include lab-grown stones, removing the requirement that a diamond must be naturally occurring. That regulatory shift reflected what scientists already knew: the origin does not change the material.

Why Lab-Grown Diamonds Are Growing So Fast

The numbers tell a compelling story. According to Fortune Business Insights, the global lab-grown diamond market reached approximately $29.5 billion in 2025 and is projected to grow at a compound annual rate of over 13% through 2034. In the United States, lab-grown diamonds now account for more than half of all engagement ring purchases, up from a negligible share just a decade ago. And a 2023 McKinsey & Company report projected that by the end of 2025, nearly 80% of Gen Z and Millennial buyers would be seeking ethically sourced or lab-grown stones.

Several factors are driving this shift:

Value. A lab-grown diamond typically costs 60 to 80% less than a comparable mined stone. That means the same budget gets you a noticeably larger or higher-quality diamond. For a couple choosing an engagement ring, that difference can be significant.

Sustainability. Growing a diamond in a lab uses a fraction of the resources required for mining. While no production method is impact-free, the environmental footprint is substantially smaller: no large-scale land disruption, dramatically less water consumption, and a supply chain that does not intersect with conflict zones.

Quality and transparency. Because the growth environment is controlled, lab-grown diamonds often have fewer inclusions and more consistent optical performance than mined stones at equivalent price points. Certification from GIA or IGI provides the same rigorous grading, so buyers can compare stones with confidence.

Shifting values. Younger consumers are redefining what luxury means. For many, a conscious choice that aligns with their values is the luxury, and paying a premium for a stone extracted from the earth no longer carries the same appeal it once did.

What to Look for When Buying a Lab-Grown Diamond

Shopping for a lab-grown diamond follows the same principles as shopping for any diamond. The 4Cs remain your guide:

• Cut is the single most important factor for how a diamond looks on your hand. A well-cut diamond handles light beautifully, returning brilliance and fire from every angle. At Miorenée, our team has been cutting and evaluating diamonds since 1986. We assess light performance the way a master cutter does: by how the stone interacts with light, not just what the certificate says.
• Color is graded on a scale from D (colorless) to Z (light yellow or brown). For most people, stones in the D to G range look colorless to the naked eye, and the savings from choosing a G over a D can be put toward a larger stone or a more detailed setting.
• Clarity measures internal characteristics (inclusions) and surface blemishes. Lab-grown diamonds frequently achieve VS2 or better clarity, meaning any inclusions are invisible without magnification.
• Carat weight refers to the diamond's weight, not its visual size (though they are related). Because lab-grown diamonds cost significantly less per carat, many buyers find they can move up in carat weight without exceeding their budget.

Beyond the 4Cs, always confirm that your diamond comes with an independent grading report from a recognized laboratory like IGI or GIA. This report is your objective record of the stone's characteristics and confirms that it is a lab-grown diamond.

A Note on Resale Value

Honesty builds trust, so here it is: lab-grown diamonds currently have a lower resale value than mined diamonds. The secondary market for lab-grown stones is still developing. If you are purchasing a diamond primarily as a financial investment, that is worth considering. But most people buy diamond jewelry to wear it, to mark a moment, to feel something every time they glance at their hand. For that purpose, a lab-grown diamond delivers the same emotional and aesthetic experience at a fraction of the cost.

Frequently Asked Questions

Can a jeweler tell if a diamond is lab-grown? Not by looking at it. Lab-grown and mined diamonds are visually identical. Specialized spectroscopic equipment can detect differences in growth patterns, but standard tools and the human eye cannot.

How long does it take to grow a diamond? A gem-quality CVD diamond typically takes two to four weeks to grow, depending on the target size and quality.

Do lab-grown diamonds come in different shapes and colors? Absolutely. Lab-grown diamonds are available in every popular shape (round, oval, emerald, cushion, pear, marquise, and more) and can also be produced in fancy colors like pink, blue, and yellow.

Curious about what a lab-grown diamond looks like in person? Explore our collection of lab-grown diamond jewelry at Miorenée and see the brilliance for yourself.

Sources

• Fortune Business Insights, Lab Grown Diamond Market Report
• The Knot, 2024 Real Weddings Study
• McKinsey & Company, 2023 diamond industry report
• U.S. Federal Trade Commission, Jewelry Guides (2018 revision)