Expedition of the All-Union PO "Soyuzkvartssamotsvety" to the Evenki NO

September 1977. USSR. Krasnoyarsk Krai. Head of the geological exploration team Anatoly Nazarov with a unique crystal of optical calcite discovered by the expedition of the All-Union Production Association "Soyuzkvartssamotsvety" of the USSR Ministry of Geology in the Nizhnyaya Tunguska region of the Evenki National Okrug. The exact date of the photo has not been established. Yuri Belozerov/TASS