mining is the basis of the oblast's economy, and mining enterprises remain the principal employers in such monotowns as apatity, kirovsk, zapolyarny, nikel, and monchegorsk. the kola mining and metallurgical company, a division of norilsk nickel, conducts nickel-, copper-, and platinum-group-metals-mining operations on the peninsula. other large mining companies include oao apatit, which is the largest producer of phosphates in europe; oao olcon, one of the leading producers of iron ore concentrates in russia; and oao kovdorsky gok, an ore-mining and processing enterprise.