Diamonds: Natural Versus Lab Grown — Which Should You Choose?
By Amber Michelle - Chief Curator & Storyteller
BARS growth apparatus. ©Gemological Institute of America. Reprinted by Permission.

It’s time to buy a diamond. You’ve heard about lab-grown diamonds and you know something about natural diamonds. What are the differences between the two and is one better than the other? We lay out the facts for you right here.

Definition of Natural and Lab-grown Diamonds

  • A natural diamond is formed over billions of years in the earth.
  • Lab-grown diamonds are created in a factory in a matter of weeks.

Both are made of carbon and they have essentially the same physical characteristics.


How Are Diamonds Made?

A natural diamond is created somewhere between 87 miles and 118 miles in the earth’s mantle when carbon containing minerals are subjected to high pressure and high temperature. Diamonds come to the surface through geological events such as volcanoes deep within the earth. Geologists estimate that It takes 1 billion to 3.3. billion years for diamonds to grow. To put that in perspective, dinosaurs roamed the planet around 230 million years ago.

There are two ways to create lab-grown diamonds.

  • The High-Pressure, High-Temperature (HPHT) method mimics the conditions of high heat and pressure that are present in the earth to form a diamond.
  • The Chemical Vapor Deposition (CVD) method of growing diamonds uses a mixture of gases in a vacuum chamber at low pressures and moderate temperatures. The gas mixture is then provided with a diamond seed. When the seed attaches to the gas it continues to reproduce itself until a diamond crystal is formed.

With both of these methods, the diamond is grown in a matter of weeks in a factory rather than in the earth by nature over billions of years.

Pricing of Lab-grown and Natural Diamonds

Pricing for natural diamonds is based on two factors: Rarity and quality of the stone.

They generally hold their value or increase in value.

In his paper “The Price of Lab-Created Diamonds Continue to Fall,” Paul Zimnisky, an independent diamond industry analyst, stated that a 1-carat lab-grown diamond, F to H color, VS clarity, VG-ideal cut with no-to-low fluorescence was selling for approximately $4,850 in March 2017. A year later the same stone is selling for $4,350, a 10 percent decline.

He noted that in the same period, the price for an equivalent natural diamond went from $5,850 to $6,150, an increase of 5 percent.

Zimnisky further states that “As lab-diamond production continues to accelerate, it seems inevitable the price spread between lab-created and natural diamonds across all sizes and qualities will continue to widen.”


How Do You Tell if a Diamond is Natural or Lab-grown?

Most companies that create lab-grown diamonds will market the stones as such. They are sometimes marked with a serial number and come with paperwork, possibly a lab report.

Detecting whether or not a diamond is natural or lab-grown takes training and the right equipment. Lab-grown diamonds have telltale signs in the structure of the stone. A gemologist in a gem laboratory with the proper equipment can identify a lab-grown diamond.

A natural diamond will often come with a gemological report that states its characteristics. It, too, is identifiable to a trained gemologist with the necessary equipment to examine the stone.

Environmental Impact of Natural and Synthetic Diamonds

In a working paper written for the Institute for Environmental Diplomacy and Security, “Ecological Comparison of Synthetic versus Mined Diamonds,” author Dr. Saleem H. Ali noted that both mining and lab-grown diamonds do have an impact on the environment.

Diamonds are generally mined and miners must go deep into the earth to recover those stones. This method is called open pit mining. The energy required to recover the diamonds will vary from mine to mine depending upon its location, climate and size of the pit.

In some places, diamonds are found in rivers. Diamonds that are found in rivers or in the ocean are known as alluvial diamonds. The amount of energy that goes into sourcing these diamonds also varies.

Oftentimes these stones are found in muddy waters by artisanal miners who pan for the stones. On the other hand, diamonds are also swept up off the ocean floor by special ships created for the purpose of recovering diamonds.

Lab-grown diamonds are made in factories that use electricity in varying amounts depending upon the method used and the materials used to create the diamond.

Natural diamonds and lab-grown diamonds both use energy and both will have an environmental impact. In his paper, Dr. Ali, Blue and Gold Distinguished Professor of Energy and the Environment at the University of Delaware, sums up the environmental impact of mined and lab-grown diamonds. “Although energy usage comparisons can provide a rough estimate of comparative impact, they vary considerably by the geographic location of the mine versus the kind of process used in the diamond synthesis.”