title: Gagates in Crimean middle jurassic sediments (Sudak): coal petrography, paleobotany, formation conditions
abstract: Background . The coal-bearing deposits of the Kopsel formation of the Bathonian-Callovian age of the Middle Jurassic near the city of Sudak (Crimea) are studied. The conducted lithological and mineralogical analysis of rocks, mainly sandstones and siltstones, with shell detritus, plant residues and coal lenses (gagates), made it possible to determine the coastal-marine and lagoon sedimentation conditions. The studied gagates are represented by structural vitrinite and belong to the humus group. 
journal: Proceedings of higher educational establishments Geology and Exploration