Grängesberg (Swedish pronunciation: [ˈɡrɛ̂ŋːɛsˌbærj]) is a locality situated in Ludvika Municipality, Dalarna County, Sweden, with 3,481 inhabitants in 2010. The town was dominated by iron-ore extraction at Grängesberg ore field (Grängesbergs malmfält) from the 16th century to 1989. In January 1990 was the last ore-train from Grängesberg to Oxelösund. Attempts to separate apatite from the ore begun in 1928 but were more clearly successful from the late 1930s to 1953. Aparite was separated by "soap flotation" (Swedish: tvålflotation). .
https://en.wikipedia.org/wiki/Gr%C3%A4ngesberg