a group of mountain ranges in the Southern Urals, Cheliabinsk Oblast, RSFSR. Maximum elevation, 748 m (Mount Il’mentau). The mountains are composed of granites and gneisses with numerous pegmatitic veins of complex and varied mineralogical composition. Among the approximately 180 minerals are ilmenite, apatite, garnet, and topaz. Pine and birch forests are found on the mountainsides. In the valleys there are meadows and swamps. The V. I. Lenin Il’men’ Preserve is situated in the Il’men’ Mountains.