Larry Paul Kelley established ICT (International Crystal Technology) in 1970 with Craig Hardy and Tom VanBergen. Kelley had worked for Dow Chemical in Ludington and at a factory in Ann Arbor that produced laser crystals. The facility was sited in Shelby because the town had a new industrial park. By 2015, Kelley was ICT's sole owner.
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, 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 factorys focus. 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. For a time, cubic zirconia was a lucrative product line; Shelby opened factories outside the United States to keep up with demand. However, the value of cubic zirconia soon declined to the point that it was used as fill when the factory was expanded. 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 factorys sales until a precipitous decline caused by the 1997 Asian financial crisis. In 1994, the factory entered the business of recrystallizing rubies, buying low-grade gems from Myanmar to be melted down in the process.
A 50-seat theater ran a presentation for visitors, and jewelry was sold on site.
The factory closed in 2019 after Kelley was diagnosed in 2017 with Alzheimer's disease. Other issues that contributed to the closing were worldwide competition and online markets. Larry Kelley died on October 24, 2020.