Lab-Grown/Synthetic, Imitation, and Assembled Gemstones: An Introduction

by Dani Chavez

In the last few years, synthetic diamonds have revolutionized the diamond markets and sent large firms, like De Beers, scrambling to keep up. Most people would be surprised to hear that synthetic gemstones and diamonds are nothing new and have a long and fascinating history.


As long as humans have mined gems and minerals, substitutes and imitations have existed. So let’s learn the difference between synthetics, imitations, and assembled stones. Synthetic gemstones are chemically, physically, and optically the same as their natural counterparts; the only difference is their creation method. Synthetic gems are created in a controlled lab environment, whereas natural gemstones are not.

Lab Grown Color Change Sapphire Ring. c/o The Gemmary

Humans have pondered gemstone synthesis since Theophrastus postulated in 315 BCE that crystals are produced from “the solidification of fluids; some through the action of heat, others through cold, and probably some by both means” (Nassau, 3). He even believed that amber is the solidification of lynx urine!

The gemstone creation theory did much better some 400 years later when Pliny the Elder wrote in his famous tome that crystal is a form of ice. Fast-forward to the mid-19th century, when gem sources and mines decreased productivity, and scientific advancement was in a renaissance with the Industrial Revolution.

Auguste Victor Louis Verneuil. c/o Wikipedia

By 1905, Auguste Victor Louis Verneuil synthesized the first jewelry-caliber ruby and spinel. His scientific studies in the late 1800s were the genesis of modern gemstone synthesis. A few years later, in 1911, he created the first synthetic sapphire and spinel using the same techniques.

After WWII, the General Electric company successfully created the first lab-grown diamond in 1955. In fact, during both World Wars, synthetics were widely popular because they were affordable, and most gem and mineral trading routes were disrupted during wartime.

Today, there are two significant methods of crystal creation: melt and solution. Melt processes, like the Czochralski or pulling method, involve melting the gemstone’s ingredients into a crucible and slowly pulling a seed crystal through the solution. Solution processes, like flux and hydrothermal, require nutrients that are dissolved and cooled to form crystals.

Common synthesized gemstones: spinel, sapphire, color-change, and star sapphire (Linde), emerald, sapphire, opal, turquoise, diamonds, onyx, lapis, alexandrite


Imitations or Simulants are crafted to mimic the gemstone’s appearance, but they are made of entirely different materials. These stimulants can be naturally occurring or shaped by humans and are very common.

Imitations gemstones are the oldest of the three, dating back 5000 years to the ancient Egyptians. Pliny the Elder recorded many “strange and artistic” names for gems, which we refer to today as “trade names” and are very misleading (Nassau, 8).

Most common imitations/simulants: glass and paste, dyed white gem material (howlite to resemble turquoise), pearls (coated beads), rhinestones, cameos, diamonds (YAG, GGG, cubic zirconia, synthetic rutile, strontium titanate, zircon, and synthetic moissanite).

Assembled Stones

Finally, assembled stones are two or three layers of material fused to create a faceted gemstone. Sometimes these doublets or triplets may contain a natural gemstone portion along with glass, plastic, colored glue, or other natural gemstones. These stones are prevalent in antique and vintage jewelry and can be detected with magnification.

Most common doublets: garnet and glass (green, red, and blue), ammolite, cameos

Most common triplets: opal (black base, thin opal, rock crystal dome), ammolite, synthetic spinel (class ring jewelry)

Most common assembled: mabe pearls, intarsias (mosaics of gemstones inlaid)

Pros of Synthetics, Imitations, and Assembled Stones

Recycling. Modern mining methods can be very destructive to the environment. Clear-cutting of tropical rainforests for diamond and gold mining is still a prevalent problem around the world. Buying a synthetic gemstone, especially a vintage or antique one, can make a small impact on the destruction of the ecosystem.

Color and Clarity. Synthetic gemstones tend to have better clarity and color than their natural counterparts. Gemstone formation in the Earth tends to trap mineral inclusions and cause feathers and fractures. Synthetics are formed in a lab-controlled environment under perfect conditions.

Price. The synthetic gemstone market is more affordable because modern mining practices, especially diamond exploration, are astronomically expensive. Scientific labs are cheaper to construct, and those savings are passed onto the buyer. 

Ethics. The elephant in the room about the gem and jewelry industry is exploitive mining practices to fund terrorism and war. Purchasing a synthetic gemstone ensures that your money is not going towards negative groups or movements.



Nassau, Kurt. (1980) Gems Made by Man. Randor, Pennsylvania: Chilton Book Company.

Smigel, Barbara PhD. (

Weldon, Robert. An Introduction to Simulants or Imitation Gem Materials. Retrieved from

Weldon, Robert. An Introduction to Synthetic Gem Materials. Retrieved from

Weldon, Robert. Gemstone Doublets, Triplets, and Other Assembled Stones. Retrieved from

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  1. […] The synthesis of rubies began in the late 19th century. In 1902, French chemist Auguste Verneuil developed a flame fusion process known as the Verneuil process to create synthetic rubies. This breakthrough allowed for the mass production of rubies with the same physical and chemical properties as natural rubies, making them more accessible for jewelry and industrial applications. Learn more in our blog post here. […]

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