The Shelby Gem Factory was the production facility of ICT Incorporated, a company in Shelby, Michigan, United States, that manufactured artificial gemstones, including simulated diamonds, rubies, sapphires, and emeralds, through proprietary processes. The gemstones were used in industrial applications, such as lasers, and for jewelry. Tours of the facility were also offered. ICT began operations in 1970 and closed in December 2019.