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In this paper we present and elaborate one research example when bauxite was the main target of the investigation. During reprocessing and reinterpretation of the original data from the "Crvene stijene" locality near Jajce in Bosnia and Herzegovina, it was established that bauxite hanging wall and footwall rocks in fact represent an even more valuable mineral resource, as "dimension stone". The final goal of the research was to optimize the ratio between research and exploration costs and total profit by exploration of all available mineral resources in the area. For that purpose, a new research evaluation method encompassing both bauxite (primary resource) and associated deposits was developed and named the "integrated approach". Integrated, joint evaluation of bauxite and associated deposits (dimension stone), gives a far greater economic significance to whole area. Finally, with this new method, the ratio between overall profit and cost will be optimized which results in significant increase in profit because all available deposits are considered for exploitation. Also this method can be applied on abandoned mining sites if there is some secondary profitable mineral deposit in the mine area.

The successful exploration of dimension stone mainly depends on the quality, size, and shape of extractable blocks of dimension stone. The investigated area is in the Pelješac Peninsula (Croatia), in the External Dinarides orogeny, built from thick carbonate succession, characterized by relatively small deposits of high-quality dimension stone. These conditions demand challenging geological investigations in the “pre-quarry” phase to find optimal quarry location. The size and shape of dimension stone blocks are mainly controlled by fracture pattern systems. In the rugged, covered terrains, it is very hard to obtain a satisfactory amount of fracture data from the surface, so it is necessary to collect them from the underground. Borehole camera technology can visualize the inner part of the rock mass and measure the fracture characteristics. The main conclusions are as follows: (1) the digital borehole camera technology provides a quick, effective, and low-cost geological survey of fractured rock mass; (2) statistical fracture distribution parameters, P10, fracture spacing, Volumetric Joint Count (Jv) based on borehole wall survey can reflect the integrity of rock mass, providing a solid decision-making base for further investment plans and dimension stone excavation method.

This paper presents a new approach to exploring bauxite deposits from underground mining works in the bauxitebearing mines of Bešpelj near Jajce in Bosnia and Herzegovina. In the area under consideration, bauxite deposits have been investigated and exploited for over 60 years. Despite the high degree of exploration in the geologically complicated structures of Bešpelj, there are numerous unexplored reserves. Up to now, they have been mainly investigated by drilling from the surface into the borehole network as dictated by legal geological regulations. Due to the increase in depths on which deposits are located and complex structural relationships, such research has become more expensive and less effective. From a geological point of view, the bauxite deposits have developed in the horizontal position. However, longlasting geological evolution from the Upper Cretaceous to the present, has brought deposits in very di erent structural positions. That is why we nd them in an inclined position, in subvertical and vertical, and often in an overturned position. For further research to become rational and e cient, a new approach of study from underground mining works was developed that will serve for study and then for the exploitation of bauxite deposits.

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