The „Žervanjska“ crushed stone diabase deposit is located on Papuk, near the town of Orahovica in the Virovitičko-Podravska County. The aim of this Master Thesis was to describe geological, mining, and geophysical explorations necessary to determine new reserves of high-quality diabase in the northwestern part of the „Žervanjska“ exploitation field. As part of the exploration works, the positions and depths of new exploration wells were determined, exploratory wells with core samples were drilled, the core of the boreholes was determined and photographed. Samples were selected for laboratory tests of physicalmechanical properties, determination of chemical composition and mineralogical and petrographic characteristics. On the exploitation field, geological mapping and measurement of the orientation of the discontinuities of the excavation fronts of the open pit mine was carried out. The rock mass of the „Žervanjska“ deposit is made up of two genetically and petrographically different members - diabase and semimetamorphites of the „Radlovac series“. At the same time, diabase is a very high-quality building material, crushed stone, while part of the „Radlovac series“ semimetamorphite deposits, primarily compact metasandstones, poorly metamorphosed quartz arenites, metaconglomerates and basalts can be used as crushed stone with lower quality requirements. The „Žervanjska“ diabase deposit has the form of an elongated volcanic body with a general NE-SW trend, embedded within the Radlovac semimetamorphic complex. The borehole profiles, geological map and geological profiles were created in the computer program Autocad LT while QGIS, Inkscape and Google Earth Pro were also used in the creation of the work. As a result of the research, a geological map, geological profiles and profiles of exploration wells B-1/21 to B-4/21 with a total depth of 187 m were created.