During 1946–1952, a marine variety of Dictyonema shale was used for uranium production in Sillamäe, Estonia, and during 1950–1989 alum shale was used in Sweden for the same purpose.
In 1946–1948, the former oil shale processing plant in Sillamäe was rebuilt by Soviets to extract uranium oxide from the locally mined Dictyonema argillite ore (a type of oil shale).