Shelby Gem Factory

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

ICT Incorporated, trade name "Shelby Gem Factory", is sited in Shelby, on the west coast of the Lower Peninsula of Michigan.[2][8] It was founded in 1970 by Larry Paul Kelley[2][7] and Craig Hardy.[9] Larry Paul Kelley and his wife Jo Kelly later retained full ownership making the Shelby Gem Factory a family business.[10][2][11][12]

The Shelby Gem Factory initially produced only synthetic ruby, with ruby lasers being the principal application, primarily sold to firms in California. However, the greater profit potential of transmuting ruby rods into gemstones led to a change in the enterprise's focus. A colorless variant crystal was developed by experimentation with different materials and proportions.[9] This was the first simulated diamond variety.[4] It became the first business anywhere to mass-produce cubic zirconia (CZ). In the 1970s the Shelby Gem Factory rode a wave of popularity CZ then enjoyed. At its peak, tons of cubic zirconia were produced for the world market. Shelby opened factories in China, India, and Panama to keep up with demand.[7]

The factory closed in 2019, after 50 years of manufacturing.[13]

Shelby Gem Factory jewelry of man-made synthetic rubies

Formerly, factory tours were offered.[14][15][16] 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.[4] Some of the furnaces burned at 5,040 °F (2,780 °C).[14]

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.[3] Exhibits on-site included a lapidary machine visitors can try 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.[4]

The public could purchase gemstone jewelry from the factory.[9] Jo Kelley, wife of Larry Paul Kelley, attributes the factory's increase in sales between 2008 and 2010 to the weak national economy.[17] [18][19]

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[4] crucible heated by surrounding electric coils. Temperatures ranged 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. Larry Kelley said it took several weeks to grow a gem crystal.[17]

The factory did not use the Verneuil method of "pulling" crystals, using temperature differences like the process that forms an icicle. Rather, it used small fragments of mined gems, which were then used as seeds to re-crystallize liquid into larger gemstones. This is the so-called Czochralski process, which is akin to chemical vapor deposition. According to Larry Kelly: "As far as I know, we are the only company on Earth that uses the second method."[4]

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.[17] 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.[17] 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.[20]

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.[9] They have a D color rating, the highest rating for diamonds (as determined by the Gemological Institute of America).[lower-alpha 2]

Although some of the company's products were "simulants", their synthetic ruby and sapphire stones were not imitations – they have the same chemical and crystalline structure that is found in natural stones. The factory's FAQ said "our rubies and sapphires are really ruby and sapphire!"[21]

The Shelby Gem Factory also manufactured simulated citrine and topaz, along with other birthstone substitutes.[4]

As per the company website's FAQ section in 2017,[21] these were the Mohs scale hardness values for some well-known gems along with Shelby gem products:

• Genuine diamond, 10
• Ruby, sapphire, Shelby ruby, and Shelby sapphire, 9
• Shelby simulated diamond ("Diamond Encore"), 8-7/8
• Shelby simulated emerald, aquamarine, and garnet, 8.6
• Genuine emerald and aquamarine, 7.5-8.0
• Genuine garnet, 6.0

The company's policy was to maintain the confidentiality of celebrity clients, of whom there are many.[1]

• Skull crucible

Wikimedia Commons has media related to Shelby Gem Factory.

• Official website
• Shelby Gem Factory pictures
• Shelby Gem Factory visit
• ICT YouTube video on explanation of semiconductor invention for making solar cells