DATA ON THE LIMANU CAVE MINERALOGY, SOUTH DOBROGEA GABRIEL DIACONU * , ŞTEFAN MARINCEA ** , DELI DUMITRAŞ ** Abstract. By means of diphractometric X-rays analyses on powders, we emphasize an association of minerals in the Limanu Cave from South Dobrogea, made up of hydroxylapatite, brushite, calcite, gypsum and dolomite as the main minerals and quartz and illite as secondary minerals. Key words: cave minerals, Limanu Cave, Dobrogea de Sud. 1. INTRODUCTION The E 95 highway, coming from Bulgaria and linking Vama Veche and Mangalia, crosses the Limanu commune situated close to the Mangalia Lake. A short distance away from the commune, in the right slope of the “La Peşteră” valley, is the entrance of the most important endokarstic void from the entire Dobrogea, namely the Peştera Limanu (Limanu Cave) (Fig. 1). Fig. 1. – Geographic position of the Peştera Limanu (after DUMITRESCU et al., 1965). The labyrinthic cave, with a total length of 3,200 m, was initially shaped naturally as a karstic plateau void, subsequently the cave was influenced by its use in the past as a limestone quarry (the cave humid atmosphere facilitating the mining) as well as a shelter until a much more recent time. The mineralogical samples were collected in places underneath bat colonies which produced the guano deposits on the floor (points 4, 22 and 25) (Fig. 2). Trav. Inst. Spéol. «Émile Racovitza», t. XLVII, p. 65–77, Bucarest, 2008