Shelby Gem Factory

Larry Paul Kelley and wife Jo Kelley, owners of the Shelby Gem Factory

Larry Paul Kelley, a native of nearby Hart, established ICT (International Crystal Technology[1]) in 1970 with business partners Craig Hardy and Tom VanBergen.[2][3] Kelley, who had lost two fingers in a chemistry accident while in college,[2] had worked for Dow Chemical in Ludington and at a factory in Ann Arbor that produced laser crystals.[4] The facility was sited in Shelby because the town had a new industrial park; the gem factory was the first tenant.[5] By 2015, Larry Kelley was ICT's sole owner.[6]

The Shelby Gem Factory initially produced only synthetic ruby, with ruby lasers being the principal application, primarily sold to firms in California. However, laser technology was in its infancy,[1] and the far greater profit potential of converting ruby rods into a variety of artificial gemstones of various colors led to a change in the factory's focus.[2] Larry Kelley built on Soviet research into cubic zirconia and became its first commercial producer, having solved issues of temperature control that had impeded its production.[1] For a time, this was a lucrative product line; Shelby opened factories in France, China, India, Thailand, and Panama to keep up with demand.[7] However, the value of cubic zirconia soon declined to the point that it was used as fill when the factory was expanded.[1] In 1983, ICT opened a faceting factory in southern China to create gemstones for jewelry use from the crystals produced in Shelby; this closed in 1991, and separate companies in China and South Korea were contracted to continue faceting. The South Korean market represented up to 40 percent of the factory's sales until a precipitous decline caused by the 1997 Asian financial crisis.[1]

In 1994, the factory entered the business of recrystallizing rubies, buying low-grade gems from Myanmar to be melted down in the process.[1]

The laboratory originally offered factory tours,[8] which were discontinued due to liability reasons stemming from the heat and light used in the process;[5] instead, a 50-seat theater and showroom was built to show visitors a presentation on the process as well as samples of its products.[3] Jewelry was also sold on site, with gold and sterling silver mounts.[5]

The factory closed in 2019 after 50 years of manufacturing. Larry Kelley had been diagnosed with Alzheimer's disease in 2017; this made him unable to continue running the business of manufacturing and selling artificial gemstones. Other issues that contributed to the closing were worldwide competition and online markets.[9] Larry Kelley died on October 24, 2020.[10]

Shelby Gem Factory jewelry of man-made synthetic rubies

Formerly, factory tours were offered.[11][12] However, they were discontinued due to liability concerns attendant to the "very high temperatures and extremely bright light" and the unavailability of affordable insurance to cover the risk.[5] Some of the furnaces burned at 5,040 °F (2,780 °C).[8]

The factory included a museum, showroom, and theater, and was a popular destination for schools, venture tours, and lapidary clubs. The 50-seat Art and Science theater showed visitors the differences between the processes that produce natural and man-made gems.[13] Exhibits on-site included a lapidary machine visitors could try, as well as a low-temperature model of a working crucible furnace. out for themselves to learn about gem cutting and a low-temperature model of a working crucible-furnace, along with photos of the factory floor which was, by then, off-limits.[5]

A cubic zirconia gem-making furnace

Cubic zirconia "run" being opened

Recrystallized natural ruby in a crucible

The gems were synthesized in a furnace. It used a US$85,000 heat resistant iridium[5] crucible heated by surrounding electric coils and produced temperatures ranging from 3,500 to 5,000 °F (1,930 to 2,760 °C). A crystal-producing mix was put into this furnace and melted. Then a slowly-spinning rod, the "seed", was lowered into the crucible, circulating the molten minerals, creating a homogeneous mixture and maintaining an even temperature throughout. Raised slowly over the course of weeks, the rotating rod cooled the liquid and allowed a large crystal to form. It took several weeks to grow a gem crystal that would be made into several small artificial gems.[14]

The factory did not use the Verneuil method of "pulling" crystals, using temperature differences like the process that forms an icicle. Rather, it used the Czochralski method, in which small fragments of mined gems were then used as seeds to re-crystallize liquid into larger gemstones, akin to chemical vapor deposition. Larry Kelley believed that his firm was the only company in the world to use this method.[5]

Shelby Gem Factory workers then cut several dozen rough gems from each crystal using a diamond saw. A rough gemstone piece was placed onto a faceting machine, where over fifty facets were cut and polished to create a finished gemstone.[14] ICT had a master jeweler on staff to mount the finished gemstones in gold settings; Larry Kelley purchased rough gold castings from out of state and finished these at the factory to make settings as needed.[14] The crystals made by the Shelby Gem Factory were used in jewelry and scientific industries worldwide. Unlike naturally-produced stones, these products were free of occlusions and internal and external flaws or inclusions.[15]

The Shelby Gem Factory's simulated diamonds were diamond simulants, which are not to be confused with lab-grown synthetic diamonds. However, they can be difficult to distinguish from real diamonds.[2] They have a D color rating, the highest rating for diamonds (as determined by the Gemological Institute of America). Although some of the company's products were "simulants", their synthetic ruby and sapphire stones were not imitations; they had the same chemical and crystalline structure that is found in natural stones. The Shelby Gem Factory also manufactured simulated citrine and topaz, along with other birthstone substitutes.[5]

As per the company website's FAQ section in 2017,[16] these were the Mohs scale hardness values for some well-known gems along with Shelby gem products:

• Genuine diamond, 10
• Shelby simulated diamond ("Diamond Encore"), 8-7/8
• Genuine emerald and aquamarine, 7.5-8.0
• Shelby simulated emerald and aquamarine, 8.6
• Genuine garnet, 6.0
• Shelby-made garnet, 8.6

• Czochralski method
• Skull crucible

Wikimedia Commons has media related to Shelby Gem Factory.

• Official website
• Shelby Gem Factory pictures
• Shelby Gem Factory visit
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