The Demidovskaya pit (№ 221) is situated in the llmeny Reserve territory, South Urals. It steeply strips dipping disseminated sulfide ore zone of 0.5 m thick in gabbroids. Chemical compositions of silicate and sulfide minerals were studied. It was established that these rocks are confined to dunite-werlite-clinopyroxenite formation. For the first time sphalerite was found in this pit. Also chrysokolla as a new mineral for the llmeny Reserve was characterized.