The increasing need of raw materials necessitates the exploitation of new deposits, potentially leading to (very) deep underground mines. With the help of fully automated machines and/ or autonomous robots it is aimed to open difficult to access deposits or re-open abandoned mines. In the past four years, the consortium of the European-wide H2020 Resilient Bio-inspired Modular Robotic Miners (ROBOMINERS) project has conducted initial baseline studies of future robotic mining machines operating in such scenarios. Technologies have been investigated, which can be applied for underground exploration and selective mining, submerged and/or operating in slurries. Throughout this project a low TRL prototype has been developed and tested, which is fully water-hydraulically powered. The prototype comprises an unconventional locomotion system, various sensors for navigation and perception, a production tool to excavate (small) amounts of soft rock material and an ore transport and-analysis system. After a multi-stage design process, a sophisticated hydraulic slurry transport system has been developed using 3D printing technology for rapid prototyping and the manufacturing of functional parts. Taking advantage of the Venturi effect, the conveying system facilitates the ore transport from the rock face to the rear of the robot and the subsequent inline analysis by means of Laser Induced Breakdown Spectrum (LIBS) technology. The testing of the full-scale prototype has been executed in an opencast oilshale mine under (partly) submerged conditions. During the field tests, the working principle of the Venturi ore transport system could be proven by successful transport of excavated oil shale up to a certain grain size. The project will serve as a guideline for future mining robots, including feasibility studies of different robot designs, potential mine layouts and mining scenarios as well as various excavation tools for different rock conditions and geophysical instruments.